Operating Segment Information - Summary of Domestic and International Operations (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Revenues [Abstract]
Revenue	$ 174,653	$ 165,676
Income from operations [Abstract]
Income from operations	31,849	54,089
Depreciation and amortization [Abstract]
Depreciation and amortization	3,987	5,283
Expenditures for property and equipment [Abstract]
Expenditures for property and equipment	2,230	11,572
Property and equipment, net [Abstract]
Property and equipment, net	45,740	40,257	$ 48,055
Assets
Assets	915,176	749,895	$ 840,537
Domestic
Revenues [Abstract]
Revenue	143,428	119,053
Income from operations [Abstract]
Income from operations	55,582	57,183
Depreciation and amortization [Abstract]
Depreciation and amortization	1,582	2,485
Expenditures for property and equipment [Abstract]
Expenditures for property and equipment	769	2,170
Property and equipment, net [Abstract]
Property and equipment, net	15,696	14,593
Assets
Assets	707,176	502,596
International
Revenues [Abstract]
Revenue	31,225	46,623
Income from operations [Abstract]
Income from operations	3,151	23,937
Depreciation and amortization [Abstract]
Depreciation and amortization	605	523
Expenditures for property and equipment [Abstract]
Expenditures for property and equipment	804	94
Property and equipment, net [Abstract]
Property and equipment, net	5,562	5,066
Assets
Assets	114,858	190,355
Corporate Services
Income from operations [Abstract]
Income from operations	(26,884)	(27,031)
Depreciation and amortization [Abstract]
Depreciation and amortization	1,800	2,275
Expenditures for property and equipment [Abstract]
Expenditures for property and equipment	657	9,308
Property and equipment, net [Abstract]
Property and equipment, net	24,482	20,598
Assets
Assets	$ 93,142	$ 56,944