Reconciliation of Benefit Obligations and Plan Assets of U.K. Plan and Japan Plan (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended			1 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Oct. 31, 2010 UNITED KINGDOM	Dec. 31, 2012 UNITED KINGDOM	Dec. 31, 2011 UNITED KINGDOM	Dec. 31, 2012 JAPAN	Dec. 31, 2011 JAPAN
Change in benefit obligation:
Projected benefit obligation at beginning of year					$ 27,335	$ 27,341	$ 1,401	$ 1,155
Service cost							121	106
Interest cost					1,359	1,486	15	18
Amendments and transfers							417
Actuarial (gains) losses					5,008	(767)	89	51
Benefits paid					(582)	(645)	(140)	(10)
Foreign currency exchange rate changes					1,593	(80)	(38)	81
Projected benefit obligation at end of year					34,713	27,335	1,865	1,401
Accumulated benefit obligation at end of year					34,713	27,335	1,539	1,124
Change in plan assets:
Fair value of plan assets at beginning of year					24,590	25,710	582	393
Actual return (loss) on plan assets					2,461	(1,247)	9	(9)
Employer contributions	1,500	1,800	1,400	800	793	802	324	188
Benefits paid					(582)	(645)	(140)	(10)
Foreign currency exchange rate changes					1,367	(30)	52	20
Fair value of plan assets at end of year					28,629	24,590	827	582
Funded status at end of year					(6,084)	(2,745)	(1,038)	(819)
Amount recognized in the financial statements consists of:
Accrued pension liabilities					6,084	2,745	1,038	819
Amounts included in accumulated other comprehensive loss not yet recognized in net periodic pension cost
Net actuarial loss					(11,197)	(7,301)	(110)	(42)
Prior service cost							(281)	(35)
Net transition obligation							(237)	(550)
Amounts expected to be amortized from accumulated other comprehensive loss into net periodic cost over the next fiscal year consists of:
Net actuarial loss					702	381
Prior service cost							16	2
Net transition obligation							$ 26	$ 42