Equity Investments - Summarized Balance Sheets of Real Estate Investments (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
ASSETS
Cash and cash equivalents	$ 112,512	$ 97,682	$ 40,952	$ 45,257
TOTAL ASSETS	1,132,324	923,163
LIABILITIES AND MEMBERS' CAPITAL
TOTAL LIABILITIES AND EQUITY	1,132,324	923,163
SoCal [Member]
ASSETS
Cash and cash equivalents		11
Real estate debt investments
Receivables and other assets		2
TOTAL ASSETS		13
LIABILITIES AND MEMBERS' CAPITAL
Other current liabilities
Members' Capital		13
TOTAL LIABILITIES AND EQUITY		13
Carrying value of the Trust's investments in the equity investments		$ 8