Company's Demand Deposits and Temporary Cash Investments (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Risks And Uncertainties [Abstract]
Deposits in FDIC and SIPC-insured institutions under insurance limits	$ 617	$ 636
Deposits in FDIC and SIPC-insured institutions over insurance limits	130,330	1,420
Deposits in foreign banks	15,303	43,664
Total cash and cash equivalents	146,250	45,720
Less outstanding checks and other reconciling items	(32,904)	(2,708)
Cash and cash equivalents	$ 113,346	$ 43,012	$ 249,509	$ 110,723