Segment Information - Selected Segment Financial Data, Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Assets	$ 1,834,342	$ 1,975,788
Americas Segment [Member] | United States [Member]
Segment Reporting Information [Line Items]
Assets	1,061,058	1,182,309
Americas Segment [Member] | Other [Member]
Segment Reporting Information [Line Items]
Assets	31,790	33,492
EMEA Segment [Member]
Segment Reporting Information [Line Items]
Assets	622,932	643,275
Asia/Pacific Segment [Member]
Segment Reporting Information [Line Items]
Assets	$ 118,562	$ 116,712