SCHEDULE III REAL ESTATE AND ACCUMULATED DEPRECIATION (Detail 2) (USD $)	12 Months Ended
	Dec. 31, 2014 item	Dec. 31, 2013 item	Dec. 31, 2012 item
Reconciliation of total real estate carrying value
Balance at Beginning of Period	$ 9,918,069,735	$ 5,978,155,929	$ 4,976,096,132
Acquisitions	1,463,440,724	4,701,785,534	1,130,059,158
Less amounts allocated to intangible assets that are included in Other Assets on our Consolidated Balance Sheets	(126,550,939)	(645,225,410)	(86,100,036)
Improvements, Etc.	5,210,401	7,226,683	4,934,558
Other (Leasing Costs and Building Adjustments as a result of net debt premiums)	523,907	6,997,768	13,081,252
Total Additions	1,342,624,093	4,070,784,575	1,061,974,932
Cost of Real Estate sold or disposed of	83,059,172	127,218,307	54,223,955
Releasing costs	732,130	251,616	582,705
Other (including Provisions for Impairment)	4,554,113	3,400,846	5,108,475
Total Deductions	88,345,414	130,870,769	59,915,135
Balance at Close of Period	11,172,348,415	9,918,069,735	5,978,155,929
Reconciliation of accumulated depreciation for the years ended:
Balance at Beginning of Period	1,121,460,394	936,019,074	816,087,890
Additions During Period - Provision for Depreciation	290,551,867	242,619,990	135,470,091
Deductions During Period: Accumulated depreciation of real estate and equipment sold or disposed of	21,203,561	57,178,670	15,538,907
Balance at Close of Period	1,390,808,700	1,121,460,394	936,019,074
Number of properties on which provisions for impairment were recorded	12	9	10
Adjustments to estimated legal obligations related to asset retirement obligations	$ 83,532	$ (64,339)	$ 30,553
Number of land leases with adjustments recorded to estimated legal obligations related to asset retirement obligations	2