Entity information:
INCOME TAXES
The components of income before income tax provision for the years ended December 31, 2017, 2016, and 2015 were as follows:
 
 
2017
 
2016
 
2015
U.S.
 
$
59.7

 
$
17.6

 
$
17.1

Non-U.S.
 
4.2

 
3.4

 
1.8

Total
 
$
63.9

 
$
21.0

 
$
18.9


The components of our income tax provision for the years ended December 31, 2017, 2016, and 2015 were as follows:
 
 
2017
 
2016
 
2015
Current Provision:
 
 
 
 
 
 
Federal
 
$
(0.5
)
 
$
(7.8
)
 
$
(11.8
)
State
 
(1.3
)
 
(1.0
)
 
(0.8
)
Foreign
 
(1.7
)
 
(1.1
)
 
(0.8
)
 
 
(3.5
)
 
(9.9
)
 
(13.4
)
Deferred Benefit:
 
 
 
 
 
 
Federal
 
(14.9
)
 
5.3

 
5.8

State
 
7.4

 
4.3

 
2.5

Foreign
 
0.2

 
0.3

 
0.2

 
 
(7.3
)
 
9.9

 
8.5

Total income tax provision
 
$
(10.8
)
 
$
—

 
$
(4.9
)

The components of our deferred income taxes as of December 31, 2017 and 2016 were as follows:
 
 
2017
 
2016
Deferred tax assets:
 
 
 
 
Federal net operating loss carryforward
 
$
7.1

 
$
0.6

State net operating loss carryforward
 
2.2

 
1.5

Research and development tax credits
 
41.2

 
6.6

Deferred rent obligation
 
7.9

 
12.4

Stock compensation
 
19.7

 
33.1

Other accrued liabilities
 
9.2

 
6.0

Deferred revenue
 
12.8

 
21.1

Other
 
1.9

 
2.4

Total gross deferred tax assets
 
102.0

 
83.7

Valuation allowance
 
(1.2
)
 
(4.1
)
Total deferred tax assets
 
100.8

 
79.6

Deferred tax liabilities:
 
 
 
 
Intangible assets
 
(22.0
)
 
(31.7
)
Capitalized software
 
(28.2
)
 
(34.9
)
Property and equipment
 
(8.8
)
 
(10.8
)
Total deferred tax liabilities
 
(59.0
)
 
(77.4
)
Net deferred tax assets
 
$
41.8

 
$
2.2


The federal NOL carryforwards expire at various times through 2036, and the state NOL carryforwards begin to expire in 2019. Our research and development, or R&D, tax credits carryforward is available to offset future federal and state taxes, and the credits expire at various times through 2036.

On December 22, 2017, President Trump enacted “H.R.1,” formerly known as the “Tax Cuts and Jobs Act” which, starting in 2018, reduces our corporate statutory income tax rate but eliminates or increases certain permanent differences. As of the date of enactment, we have adjusted our deferred tax assets and liabilities for our new statutory rate which resulted in a $3.0 million credit to our income tax provision for the year ended December 31, 2017. In addition, we have estimated and recorded a $0.4 million repatriation transition tax related to our foreign operations that increased our income tax provision, and made a significant judgment related to the fact that our current equity arrangements with our covered employees meet the requirements of the transition rule which resulted in minimal adjustments to our deduction estimates for highly compensated employees in the current year.
As discussed in Note 1 – Nature of Operations and Summary of Significant Accounting Policies, we adopted new accounting guidance related to accounting for stock-based compensation on January 1, 2017. During the years ended December 31, 2016, and 2015, we utilized tax attributes to reduce the current tax provision by $9.0 million, and $12.9 million, respectively. As of December 31, 2016, we had federal and state NOL carryforwards of approximately $72.2 million (which was comprised entirely of NOL carryforwards from deductions related to stock-based compensation) and $50.5 million (which included $19.2 million of NOL carryforwards from stock-based compensation), respectively, to offset future federal and state taxable income. During the years ended December 31, 2016 and 2015, we recorded excess tax benefits from federal and state tax deductions of $7.5 million and $10.3 million, respectively, as a component of additional paid-in capital.
A reconciliation of the federal statutory income tax rate to our effective income tax rate for the years ended December 31, 2017, 2016, and 2015 is as follows:
 
 
2017
 
2016
 
2015
Income tax computed at federal statutory tax rate
 
35
 %
 
35
 %
 
35
 %
State taxes, net of federal benefit
 
4
 %
 
4
 %
 
7
 %
Research and development credits
 
(14
)%
 
(46
)%
 
(32
)%
Permanent differences
 
5
 %
 
7
 %
 
13
 %
Tax benefits from stock-based compensation
 
(3
)%
 
—
 %
 
—
 %
Impact of enacted tax reform
 
(4
)%
 
—
 %
 
—
 %
Valuation allowance
 
(6
)%
 
—
 %
 
3
 %
Effective income tax rate
 
17
 %
 
—
 %
 
26
 %

A reconciliation of the beginning and ending amount of uncertain tax benefits is as follows:
 
 
2017
 
2016
 
2015
Beginning uncertain tax benefits
 
$
9.8

 
$
7.7

 
$
5.8

Prior year – increases
 
0.2

 
0.6

 
0.5

Current year – decreases
 
—

 
(0.6
)
 
(0.4
)
Current year – increases
 
2.5

 
2.1

 
1.8

Ending uncertain tax benefits
 
$
12.5

 
$
9.8

 
$
7.7


Included in the balance of unrecognized tax benefits at December 31, 2017 are $11.5 million of tax benefits that, if recognized, would affect the effective tax rate. We anticipate that no material amounts of unrecognized tax benefits will either expire or be settled within 12 months of the reporting date.
There were no interest and penalties included in the tax provision for the years ended December 31, 2017 and December 31, 2015. Interest and penalties included in the tax provision amounted to a credit of $0.3 million for the year ended December 31, 2016. Accrued interest and penalties amounted to $1.1 million as of both December 31, 2017 and 2016, respectively.
We are subject to taxation in Federal, various state, and Indian jurisdictions. All carryforward attributes generated in prior years may still be adjusted upon examination by the Internal Revenue Service or other tax authorities if they have been used or will be used in a future period. As of December 31, 2017, federal tax years after 2014, state tax years after 2013, and foreign tax years after 2009 remain open per the statute of limitations by the major taxing jurisdictions to which we are subject.