Schedule of Assets for Reportable Segments (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Total assets	$ 2,936,375	$ 2,974,742
Owned and managed
Segment Reporting Information [Line Items]
Total assets	2,638,260	2,654,791
Managed-only
Segment Reporting Information [Line Items]
Total assets	95,361	119,191
Corporate and Other
Segment Reporting Information [Line Items]
Total assets	$ 202,754	$ 200,760