Income Taxes - Components of Current and Deferred Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
Federal	$ 14,515	$ 1,598
State and local	1,425	2,431	$ 94
Foreign	567	210
Total current	16,507	4,239	94
Deferred:
Federal	10,629	46,784	10,739
State and local	2,296	6,233	1,664
Foreign	(25)	(123)
Total deferred	12,900	52,894	12,403
Income tax expense from operations	$ 29,407	$ 57,133	$ 12,497

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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