Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Real estate properties:
Land	$ 178,931		$ 161,875
Buildings, improvements and lease intangibles	2,861,935		2,625,538
Personal property	9,267		8,739
Land held for development	17,054		25,171
Total real estate properties	3,067,187		2,821,323
Less accumulated depreciation	(632,109)		(580,617)
Total real estate properties, net	2,435,078		2,240,706
Cash and cash equivalents	8,671		6,776
Mortgage notes receivable	125,547	[1]	162,191	[1]
Assets held for sale and discontinued operations, net	6,852		3,337
Other assets, net	153,514		126,962
Total assets	2,729,662		2,539,972
Liabilities:
Notes and bonds payable	1,348,459	[2]	1,293,044	[2]
Accounts payable and accrued liabilities	73,741		65,678
Liabilities of discontinued operations	1,112		131
Other liabilities	61,064		60,175
Total liabilities	1,484,376		1,419,028
Commitments and contingencies
Stockholders' Equity:
Preferred stock, $.01 par value; 50,000 shares authorized; none issued and outstanding	0		0
Common stock, $.01 par value; 150,000 shares authorized; 95,924 and 87,514 shares issued and outstanding at December 31, 2013 and 2012, respectively.	959		875
Additional paid-in capital	2,325,228		2,100,297
Accumulated other comprehensive income (loss)	51		(2,092)
Cumulative net income attributable to common stockholders	808,362		801,416
Cumulative dividends	(1,891,123)		(1,779,552)
Total stockholders’ equity	1,243,477		1,120,944
Noncontrolling interests	1,809		0
Total equity	1,245,286		1,120,944
Total liabilities and equity	$ 2,729,662		$ 2,539,972

[1] Level 2 - Fair value based on quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-driven valuations in which significant inputs and significant value drivers are observable in active markets.

[2] Level 3 - Fair value derived from valuation techniques in which one of more significant inputs or significant value drivers are unobservable.