Schedule of Total Assets (Detail) - Entity [Domain] - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Total assets	$ 3,175,166	$ 3,127,191
Owned and managed
Segment Reporting Information [Line Items]
Total assets	2,820,603	2,745,905
Managed-only
Segment Reporting Information [Line Items]
Total assets	65,267	68,146
Corporate and Other
Segment Reporting Information [Line Items]
Total assets	$ 289,296	$ 313,140