Components of Deferred Tax Assets and Deferred Tax Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets
Tax credits and loss carryforwards	$ 260	$ 563
Accrued liabilities	9,852	9,211
Incentive compensation	21,206	24,682
Other	4,084	3,909
Deferred Tax Assets, Gross	35,402	38,365
Deferred tax liabilities
Property, plant and equipment	(5,823)	(4,000)
Intangibles	(5,299)	(5,325)
Prepaid assets	(689)	(697)
Convertible note discount	(715)	(3,234)
Other	(1,860)	(1,658)
Deferred tax liability	(14,386)	(14,914)
Net deferred tax asset before valuation allowances and reserves	21,016	23,451
Valuation allowances	(1,172)	(1,159)
Net deferred tax asset	$ 19,844	$ 22,292