Entity information:
INCOME TAXES
The income tax expense included in the accompanying statements of income consists of the following (in thousands):
 
 
Years Ended December 31,
 
 
2017
 
2016
 
2015
Current income tax expense
 
$
12,607

 
$
8,557

 
$
10,671

Deferred income tax expense (benefit)
 
3,514

 
1,768

 
(3,392
)
Income tax expense
 
$
16,121

 
$
10,325

 
$
7,279



The components of the net deferred tax asset (liability) as of December 31, 2017 and 2016 are summarized below (in thousands):
 
 
Assets
 
Liabilities
Allowance for loan losses
 
$
4,364

 
$
Retirement and other benefit plans
 
 

 
(2,102
)
Premises and equipment
 
 
 
(5,716
)
Core deposit intangible
 
 
 
(3,660
)
Unrealized losses on securities available for sale
 
4,285

 
 
Effective hedging derivatives
 
 
 
(1,701
)
Fair value adjustment on loans
 
2,607

 
 
Fair value adjustment on time deposits
 
 
 
(54
)
Alternative minimum tax credit
 
6,943

 
 
Unfunded status of defined benefit plan
 
7,018

 
 

State business tax credit
 
544

 
 

Stock-based compensation
 
642

 
 

Other
 


 
(966
)
Gross deferred tax assets (liabilities)
 
26,403


(14,199
)
Net deferred tax asset at December 31, 2017
 
$
12,204

 
 

 
 
 
 
 
Allowance for loan losses
 
$
6,269

 
$
Retirement and other benefit plans
 
 

 
(2,707
)
Premises and equipment
 
 

 
(5,273
)
Core deposit intangible
 
 
 
(1,576
)
Unrealized losses on securities available for sale
 
12,286

 


Effective hedging derivatives
 
 
 
(2,474
)
Fair value adjustment on loans
 
1,404

 
 
Alternative minimum tax credit
 
8,776

 
 
Unfunded status of defined benefit plan
 
10,436

 
 

State business tax credit
 
604

 
 

Stock-based compensation
 
995

 
 

Other
 
151

 
 

Gross deferred tax assets (liabilities)
 
40,921

 
(12,030
)
Net deferred tax asset at December 31, 2016
 
$
28,891

 
 



A reconciliation of tax at statutory rates and total tax expense is as follows (dollars in thousands):
 
 
Years Ended December 31,
 
 
2017
 
2016
 
2015
 
 
Amount
 
Percent of Pre-Tax Income
 
Amount
 
Percent of Pre-Tax Income
 
Amount
 
Percent of Pre-Tax Income
Statutory tax expense
 
$
24,652

 
35.0
 %
 
$
20,886

 
35.0
 %
 
$
17,946

 
35.0
 %
Increase (decrease) in taxes from:
 
 

 
 

 
 

 
 

 
 

 
 

Tax rate changes
 
2,416

 
3.4
 %
 

 

 

 

Tax exempt interest
 
(10,195
)
 
(14.5
)%
 
(9,879
)
 
(16.6
)%
 
(9,975
)
 
(19.5
)%
Bank owned life insurance
 
(885
)
 
(1.2
)%
 
(915
)
 
(1.5
)%
 
(914
)
 
(1.8
)%
Share-based compensation
 
(482
)
 
(0.7
)%
 

 

 
(75
)
 
(0.1
)%
Acquisition costs
 
467

 
0.7
 %
 

 

 

 

State business tax
 
68

 
0.1
 %
 
71

 
0.1
 %
 

 

Other, net
 
80

 
0.1
 %
 
162

 
0.3
 %
 
297

 
0.6
 %
Income tax expense
 
$
16,121

 
22.9
 %
 
$
10,325

 
17.3
 %
 
$
7,279

 
14.2
 %


The Tax Cuts and Jobs Act was enacted on December 22, 2017. The Act reduces the U.S. federal corporate tax rate from 35% to 21%. We remeasured certain deferred tax assets and liabilities based on the rates at which they are expected to reverse in the future, which is generally 21%. However, we are still analyzing certain aspects of the Act and refining our calculations, which could potentially affect the measurement of these balances or potentially give rise to new deferred tax amounts. The provisional amount recorded related to the remeasurement of our net deferred tax asset balance was $2.4 million, an increase to the effective tax rate (“ETR”) of 3.4%.

The Tax Cuts and Jobs Act repealed the existing Alternative Minimum Tax (“AMT”). As of December 31, 2017, we had a remaining AMT tax credit of $6.9 million. This existing tax credit carryforward can be used to offset regular future tax liability. Additionally, this AMT credit is refundable in any taxable year after 2017 and before 2022 in an amount equal to 50% of the excess of the minimum tax credit for the taxable year over the amount of the credit allowable for the year against regular tax liability. We expect to realize the remaining AMT tax credit in 2018 to offset tax liability.

During the first quarter of 2017, we adopted a new accounting standard that impacted how the income tax effects associated with stock-based compensation are recognized. See “Note 1 - Summary of Significant Accounting and Reporting Policies” for additional information. The adoption of the standard reduced income tax expense by $482,000 and the ETR by 0.7% for the year ended December 31, 2017.

We file income tax returns in the U.S. federal jurisdiction and in certain states.  We are no longer subject to U.S. federal income tax examinations by tax authorities for years before 2014 or Texas state tax examinations by tax authorities for years before 2013.  No valuation allowance for deferred tax assets was recorded at December 31, 2017 or 2016 as management believes it is more likely than not that all of the deferred tax assets will be realized in future years. Unrecognized tax benefits were not material at December 31, 2017 or 2016.