Restatement of Consolidated Financial Statements - Schedule of Restatement Adjustments and Impact on Previously Reported Consolidated Retained Earnings (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jan. 01, 2011
Retained earnings	$ 105,889	$ 170,092	$ 60,054	$ 71,355
As Previously Reported [Member]
Retained earnings		287,251	93,950	72,157
Adjustments [Member]
Retained earnings		(117,159)	(33,896)	(802)
Adjustments [Member] | Understated Employee Benefits [Member]
Retained earnings		(4,740)	(3,830)	(1,358)
Adjustments [Member] | Other Revenue Recognition - Non-recurring Engineering [Member]
Retained earnings				835
Adjustments [Member] | Accrued Liabilities [Member]
Retained earnings				(221)
Adjustments [Member] | Inventory Reserves And Other [Member]
Retained earnings				$ (58)