Segment Reporting - Schedule of Financial Results by Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Revenues:
Rental income	$ 293,739	$ 313,971
Direct financing lease income	433	569
Operating expense reimbursements	26,726	23,247
Total revenues	348,029	369,020
Operating expenses:
Cole Capital reallowed fees and commissions	2,660	8,068
Acquisition-related	617	242
Litigation and other non-routine costs, net of insurance recoveries	12,875	(5,175)
Property operating	34,016	34,813
General and administrative	29,148	29,400
Depreciation and amortization	183,152	204,308
Impairment of real estate	6,725	160,517
Total operating expenses	269,193	432,173
Operating income (loss)	78,836	(63,153)
Other (expense) income:
Interest expense	(73,743)	(80,426)
Loss on extinguishment and forgiveness of debt, net	(70)	0
Other income, net	798	1,062
Equity in (loss) income and gain on disposition of unconsolidated entities	(82)	10,404
Gain (loss) on derivative instruments, net	824	(1,086)
Total other expenses, net	(72,273)	(70,046)
Income (loss) before taxes and real estate dispositions	6,563	(133,199)
Income (loss) before taxes	19,044	(116,024)
(Provision for) benefit from income taxes	(4,254)	(56)
Net income (loss)	14,790	(116,080)
Company Total [Abstract]
Total revenues	348,029	369,020
Total operating expenses	(269,193)	(432,173)
Total other expenses, net	(72,273)	(70,046)
Net income (loss)	14,790	(116,080)
Total Assets	15,356,535		$ 15,587,574
REI segment [Member]
Revenues:
Rental income	293,739	313,971
Direct financing lease income	433	569
Operating expense reimbursements	26,726	23,247
Total revenues	320,898	337,787
Operating expenses:
Acquisition-related	617	217
Litigation and other non-routine costs, net of insurance recoveries	12,875	(5,175)
Property operating	34,016	34,813
General and administrative	12,560	12,228
Depreciation and amortization	178,297	195,991
Impairment of real estate	6,725	160,517
Total operating expenses	245,090	398,591
Operating income (loss)	75,808	(60,804)
Other (expense) income:
Interest expense	(73,743)	(80,426)
Loss on extinguishment and forgiveness of debt, net	(70)	0
Other income, net	670	568
Equity in (loss) income and gain on disposition of unconsolidated entities	(82)	10,404
Gain (loss) on derivative instruments, net	824	(1,086)
Total other expenses, net	(72,401)	(70,540)
Income (loss) before taxes and real estate dispositions	3,407	(131,344)
Gain on disposition of real estate and held for sale assets, net	12,481	17,175
Income (loss) before taxes	15,888	(114,169)
(Provision for) benefit from income taxes	(3,108)	(1,365)
Net income (loss)	12,780	(115,534)
Company Total [Abstract]
Total revenues	320,898	337,787
Total operating expenses	(245,090)	(398,591)
Total other expenses, net	(72,401)	(70,540)
Net income (loss)	12,780	(115,534)
Total Assets	15,110,337		15,337,623
Cole Capital segment [Member]
Revenues:
Offering-related fees and reimbursements	4,316	12,391
Transaction service fees and reimbursements	4,097	2,384
Management fees and reimbursements	18,718	16,458
Total revenues	27,131	31,233
Operating expenses:
Cole Capital reallowed fees and commissions	2,660	8,068
Acquisition-related	0	25
General and administrative	16,588	17,172
Depreciation and amortization	4,855	8,317
Total operating expenses	24,103	33,582
Operating income (loss)	3,028	(2,349)
Other (expense) income:
Total other expenses, net	128	494
Income (loss) before taxes	3,156	(1,855)
(Provision for) benefit from income taxes	(1,146)	1,309
Net income (loss)	2,010	(546)
Company Total [Abstract]
Total revenues	27,131	31,233
Total operating expenses	(24,103)	(33,582)
Total other expenses, net	128	494
Net income (loss)	2,010	$ (546)
Total Assets	$ 246,198		$ 249,951