Segment Information - Selected Segment Financial Data, Revenues and Income Before Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Revenues	$ 308,637	$ 238,701	$ 265,822	$ 232,817	$ 290,224	$ 249,644	$ 254,808	$ 221,473	$ 1,045,977	$ 1,016,149	$ 864,928
Depreciation and amortization expense									97,431	86,683	69,967
Stock-based compensation expense									18,380	11,045	13,572
Income (loss) before taxes	$ 62,623	$ 18,566	$ 32,876	$ (692)	$ 69,700	$ 25,165	$ 13,646	$ (9,742)	113,373	98,769	93,159
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization expense									67,044	60,200	44,053
Stock-based compensation expense									15,483	7,467	10,128
Income (loss) before taxes									(172,185)	(199,583)	(173,782)
Americas - United States [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues									628,013	614,488	450,251
Americas - Other [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues									82,548	87,279	91,639
EMEA [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues									250,568	230,879	228,679
Depreciation and amortization expense									3,670	4,126	6,310
Stock-based compensation expense									1,223	419	759
Income (loss) before taxes									132,518	116,120	87,522
Asia/Pacific [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues									84,848	83,503	94,359
Depreciation and amortization expense									1,751	1,809	2,574
Stock-based compensation expense									36	249	293
Income (loss) before taxes									41,658	38,853	33,923
Americas [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization expense									24,966	20,548	17,030
Stock-based compensation expense									1,638	2,910	2,392
Income (loss) before taxes									$ 111,382	$ 143,379	$ 145,496