Real Estate Joint Ventures - Summarized Statements of Operations for Unconsolidated Investments (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Investments in and Advances to Affiliates [Line Items]
Total expenses, net	$ 188,623	$ 130,479	$ 137,262
Net loss	406,282	4,966	5,990
Statements Of Operations
Investments in and Advances to Affiliates [Line Items]
Total expenses, net	1,952	1,014	1,042
Net loss	$ 1,952	$ 1,014	$ 1,042