Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Cash flows from operating activities:
Net income (loss)	$ 15,617	$ (19,620)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation, amortization and other	57,577	56,966
Share-based compensation expense	4,663	7,647
Bad debt expense	10	476
Change in fair value of derivative financial instruments	(10,528)	5,295
Changes in operating assets and liabilities:
Receivables and other assets	(4,497)	(4,122)
Accounts payable and accrued liabilities	4,892	1,297
Security deposits, prepaid rent and other liabilities	4,084	(78)
Net cash provided by operating activities	71,818	47,861
Cash flows from investing activities:
Acquisition of real estate operating properties and other assets	(94,139)	(213,900)
Capital expenditures	(6,110)	(12,349)
Restricted cash, escrow deposits and notes receivable	(645)	(511)
Release of restricted cash	0	580
Real estate deposits paid	0	(2,810)
Real estate deposits used	0	3,800
Net cash used in investing activities	(100,894)	(225,190)
Cash flows from financing activities:
Proceeds from unsecured senior notes	297,558	0
Borrowings on unsecured revolving credit facility	103,000	268,000
Payments on unsecured revolving credit facility	(175,000)	(268,000)
Borrowings on unsecured term loans	0	300,000
Payments on secured real estate term loan and mortgage loans	(148,672)	(79,774)
Deferred financing costs	(3,011)	(4,934)
Derivative financial instrument termination payments	(1,195)	0
Security deposits	0	193
Proceeds from issuance of common stock, net	125,584	0
Repurchase and cancellation of common stock	(272)	(31,935)
Dividends	(63,098)	(51,237)
Payment on earnout liability	(92)	(328)
Distributions to noncontrolling interest of limited partners	(811)	(170)
Net cash provided by financing activities	133,991	131,815
Net change in cash and cash equivalents	104,915	(45,514)
Cash and cash equivalents - beginning of period	15,956	69,491
Cash and cash equivalents - end of period	$ 120,871	$ 23,977