Consolidated Balance Sheets (Parenthetical) (USD $)
In Thousands, except Share data, unless otherwise specified
Dec. 31, 2012
Dec. 31, 2011
Statement of Financial Position [Abstract]    
Accumulated depreciation on buildings & improvements $ 297,422 $ 238,688
Unearned income on real estate assets under direct financing leases 11,454 13,342
Accumulated amortization on acquired intangible lease assets 159,639 128,544
Allowance for doubtful accounts on rents and tenant receivables 80 547
Accumulated amortization on deferred financing costs 20,499 17,751
Accumulated amortization on acquired below market lease intangibles $ 53,557 $ 42,880
Preferred stock, par value $ 0.01 $ 0.01
Preferred stock, shares authorized 10,000,000 10,000,000
Preferred stock, shares issued 0 0
Preferred stock, shares outstanding 0 0
Common stock, par value $ 0.01 $ 0.01
Common stock, shares authorized 240,000,000 240,000,000
Common stock, shares issued 208,597,575 210,151,692
Common stock, shares outstanding 208,597,575 210,151,692