Income Taxes - Reconciliation of Statutory Federal Income Tax Rate to Effective Income Tax Rate (Detail)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Federal rate	35.00%	35.00%	35.00%
State and local income taxes, net of federal income tax benefit	0.60%	1.30%	1.60%
Leverage lease adjustment	(1.30%)	(1.10%)	(2.10%)
Tax-exempt income	(2.50%)	(3.30%)	(3.10%)
Foreign operations	(6.60%)	(3.00%)	(4.40%)
Tax credits	(1.40%)	(0.80%)	(2.00%)
Tax litigation	(0.00%)	(0.00%)	16.50%
Carryback claim	(0.00%)	(4.70%)	(0.00%)
Nondeductible litigation expense	0.00%	2.10%	0.00%
Other – net	0.10%	0.10%	0.60%
Effective tax rate	23.90%	25.60%	42.10%

Effective Income Tax Rate Reconciliation, Carryback Claim

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Effective Income Tax Rate Reconciliation, Nondeductible Expense, Litigation, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income (loss) exempt from income taxes.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax settlements. Including, but not limited to, domestic tax settlement, foreign tax settlement, state and local tax settlement, and other tax settlements.

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