Slicers (applies to each fact value in each table cell)

Reporting Entity [Axis]

0000040888 (http://www.sec.gov/CIK)

Income Tax Disclosure [Abstract]	Period [Axis]
	2016-01-01 - 2016-12-31
Income Tax Disclosure [Abstract]
Summary of Components of Company's Income Tax Provision (Benefit) from Continuing Operations	The components of the Company’s income tax provision from continuing operations:   Year Ended   One month ended   December 31,   November 30,   November 30,   December 31,   2016   2015   2014   2015   (In millions) Current                  U.S. federal $ 3.2   $ 33.0   $ 19.0   $ 7.9    State and local 3.2   3.4   4.1   1.2   6.4   36.4   23.1   9.1 Deferred                  U.S. federal 2.8   (41.2 )   (5.5 )   (6.2 )    State and local 2.0   5.1   (1.3 )   (0.9 )   4.8   (36.1 )   (6.8 )   (7.1 ) Income tax provision $ 11.2   $ 0.3   $ 16.3   $ 2.0
Schedule of Reconciliation of U.S. Federal Statutory Income Tax Rate to Effective Income Tax Rate on Earnings	A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate on earnings from continuing operations was as follows:   Year Ended    One month ended   December 31,   November 30,   November 30,   December 31,   2016   2015   2014   2015 Statutory U.S. federal income tax rate - provision (benefit) 35.0  %   (35.0 )%   (35.0 )%   35.0  % State and local income taxes, net of U.S. federal income tax effect (2.3 )   16.2   11.4   4.8 Changes in state income tax rates 13.4   19.0   (0.7 )   0.1 Reserve adjustments (1.0 )   2.2   (0.8 )   (0.3 ) Valuation allowance adjustments —   —   0.3   — Rescindable common stock interest and realized losses —   —   0.9   — Non-deductible convertible subordinated notes interest 2.9   8.0   7.0   1.2 Non-deductible premiums on repurchase of convertible subordinated notes —   —   64.1   — R&D credits (14.1 )   —   4.0   (2.8 ) Retroactive change in federal tax law —   (11.6 )   —   (19.4 ) Benefit of manufacturing deductions 1.5   (5.8 )   (4.3 )   (7.0 ) Lobbying costs 2.7   3.6   1.0   0.4 Deferred tax adjustment (1.3 )   —   —   7.8 Other, net 1.4   5.2   1.5   2.4 Effective income tax rate - provision 38.2  %   1.8  %   49.4  %   22.2  %
Schedule of Reconciliation of Change in Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits consisted of the following:   Year Ended    One month ended   December 31,   November 30,   November 30,   December 31,   2016   2015   2014   2015   (In millions) Balances at beginning of fiscal year $ 7.1   $ 6.8   $ 7.9   $ 6.7   Increases based on tax positions in prior years 25.8   1.0   0.6   0.6   Decreases based on tax position in prior years (1.2 )   (1.8 )   (1.3 )   (0.2 )   Increases based on tax positions in current year 0.7   0.7   —   —   Lapse of statute of limitations (2.9 )   —   (0.4 )   — Balances at end of fiscal year $ 29.5   $ 6.7   $ 6.8   $ 7.1
Summary of Deferred Tax Assets and Liabilities	Deferred tax assets and liabilities were as follows:   As of December 31,     2016   2015   (In millions) Deferred Tax Assets           Accrued estimated costs $ 89.1   $ 113.3     Basis difference in assets and liabilities 8.5   6.0     Tax losses and credit carryforwards 6.5   3.8     Net cumulative defined benefit pension plan losses 212.9   227.8     Retiree medical and life insurance benefits 16.2   19.6     Valuation allowance (1.7 )   (1.2 )         Total deferred tax assets 331.5   369.3 Deferred Tax Liabilities            Revenue recognition differences 21.7   30.7      Basis differences in intangible assets 17.3   13.8          Total deferred tax liabilities 39.0   44.5          Total net deferred tax assets $ 292.5   $ 324.8
Summary of Changes in Valuation Allowance	The changes in the Company's valuation allowance by period was as follows:   Balance at Beginning of Period  Tax Valuation Allowance Charged to Income Tax Provision  Tax Valuation Allowance Credited to Income Tax Provision  Balance at End of Period    (In millions) Fiscal 2016 $ 1.2 $ 0.5 $ — $ 1.7 One month ended December 31, 2015 1.7 — (0.5 ) 1.2 Fiscal 2015 2.6 0.6 (1.5 ) 1.7 Fiscal 2014 2.6 — — 2.6