Consolidated Total Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	$ 200,969	$ 56,772	$ 92,027	$ 101,905
Assets	2,794,906	2,735,406
Operating Segments
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	2,593,937	2,678,634
Operating Segments | Domestic
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	2,130,996	2,139,972
Operating Segments | International
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	462,941	538,662
Segment Reconciling Items
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents	$ 200,969	$ 56,772