Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Income - Summary of Change in Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			$ 622,442
Net income (loss)	$ 8,840	$ (2,597)	6,539	$ (9,027)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	0	0	0	0
Other comprehensive loss - unrealized loss on valuation of swap agreements	(15,388)	3,973	(51,347)	12,576
Reclassification of realized interest on swap agreements	(288)	(55)	(1,374)	417
Noncontrolling interest distributions	(29,713)	(9,014)	(34,595)	(24,654)
Employee Long-term Incentive Plan Unit Awards	1,916	2,219	7,361	8,332
Reallocation of noncontrolling interests	0	0	0	0
Ending Balance	709,941		709,941
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	618,910	619,874	622,442	648,440
Distributions declared of $0.28, 0.27 and $0.84, $0.81 per Common OP Unit for three and nine months ended September 30, 2019 and 2018, respectively	(1,765)	(1,692)	(5,322)	(5,126)
Net income (loss)	(1,618)	(11,822)	(25,196)	(33,336)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	(720)	(834)	(4,230)	(1,957)
Other comprehensive loss - unrealized loss on valuation of swap agreements	(1,115)	702	(8,006)	2,060
Reclassification of realized interest on swap agreements	7	87	(61)	280
Noncontrolling interest contributions	129,438	40,440	161,628	46,990
Noncontrolling interest distributions	(29,713)	(9,014)	(34,595)	(24,654)
Employee Long-term Incentive Plan Unit Awards	1,768	2,082	6,965	7,924
Reallocation of noncontrolling interests	(5,251)	(1,783)	(3,684)	(2,581)
Ending Balance	709,941	638,040	709,941	638,040
Noncontrolling Interests | Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ending Balance	(3,684)		(3,684)
Noncontrolling Interests | Noncontrolling Interests in Partially-Owned Affiliates
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	515,205	514,774	518,219	545,519
Distributions declared of $0.28, 0.27 and $0.84, $0.81 per Common OP Unit for three and nine months ended September 30, 2019 and 2018, respectively	0	0	0	0
Net income (loss)	(2,403)	(12,554)	(27,633)	(35,313)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	0		0	0
Other comprehensive loss - unrealized loss on valuation of swap agreements	(251)	505	(5,320)	1,435
Reclassification of realized interest on swap agreements	23	96		270
Noncontrolling interest contributions	129,438	40,440	161,628	46,990
Noncontrolling interest distributions	(29,713)	(9,014)	(34,595)	(24,654)
Employee Long-term Incentive Plan Unit Awards	0	0	0	0
Reallocation of noncontrolling interests	0	0	0	0
Ending Balance	612,299	534,247	612,299	534,247
Noncontrolling Interests | Noncontrolling Interests in Partially-Owned Affiliates | Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ending Balance	0		0
Noncontrolling Interests | Operating Partnership, as General Partner or Managing Member
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	103,705	105,100	104,223	102,921
Distributions declared of $0.28, 0.27 and $0.84, $0.81 per Common OP Unit for three and nine months ended September 30, 2019 and 2018, respectively	(1,765)	(1,692)	(5,322)	(5,126)
Net income (loss)	785	732	2,437	1,977
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	(720)	(834)	(4,230)	(1,957)
Other comprehensive loss - unrealized loss on valuation of swap agreements	(864)	197	(2,686)	625
Reclassification of realized interest on swap agreements	(16)	(9)	(61)	10
Noncontrolling interest contributions		0	0	0
Noncontrolling interest distributions	0	0	0	0
Employee Long-term Incentive Plan Unit Awards	1,768	2,082	6,965	7,924
Reallocation of noncontrolling interests	(5,251)	(1,783)	(3,684)	(2,581)
Ending Balance	97,642	$ 103,793	97,642	$ 103,793
Noncontrolling Interests | Operating Partnership, as General Partner or Managing Member | Restatement Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ending Balance	$ (3,684)		$ (3,684)