Income Taxes - Schedule of Income Tax Expense as Percentage of Pre-Tax Earnings (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income taxes at statutory rate	35.00%	35.00%	35.00%
Valuation allowance on foreign tax credits	(33.00%)
Valuation allowance on state net operating loss carryforwards	(19.00%)
Valuation allowance reversal- investment in foreign entity		(1.00%)
Change in tax rate on deferred items	18.00%	3.00%
State income taxes, net of federal benefit	5.00%		2.00%
Other items - net	(4.00%)	1.00%	1.00%
Total	2.00%	38.00%	38.00%
Income taxes at statutory rate	$ (9,502)	$ 15,140	$ 18,590
Increase (decrease) in taxes resulting from:
Valuation allowance on foreign tax credits	8,991		113
Valuation allowance on state net operating loss carryforwards	5,028
Valuation allowance reversal- investment in foreign entity		(456)
Change in tax rate on deferred items	(4,772)	1,078
State income taxes, net of federal benefit	(1,384)	146	916
Other items - net	1,170	424	808
Total	$ (469)	$ 16,332	$ 20,427

Effective income tax rate reconciliation state valuation allowance.

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Increase Decrease In Taxes [Abstract]

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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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