Assets and Liabilities of Consolidated Variable Interest Entities (Parenthetical) (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Variable Interest Entity [Line Items]
Real estate, accumulated depreciation	$ 112,325	$ 97,392
Deferred financing costs, accumulated amortization	17,080	15,811
Indebtedness, fair value	316,620	216,703
Variable Interest Entities
Variable Interest Entity [Line Items]
Real estate, accumulated depreciation	2,341	1,941
Deferred financing costs, accumulated amortization	15,010	13,633
Indebtedness, fair value	$ 304,687	$ 187,048