Earnings per Share and Unit (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
	Jul. 15, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income per common unit - diluted
Weighted Average Limited Partnership Units Outstanding, Basic		154,170,000	154,170,000	154,170	154,170,000
Parent Company [Member]
Earnings Per Share [Abstract]
Income from operations		$ 1,534	$ 31,979	$ 82,337	$ 94,789
Gain on sale of real estate, net of tax				22,997	34,215
Net income attributable to common stockholders		$ 5,305	$ 53,731	$ 87,992	$ 111,384
Weighted average common units outstanding for basic EPU (in shares)		103,675,000	94,158,000	99,639,000	94,080,000
Weighted average common units outstanding for diluted EPU (in shares)		104,255,000	94,595,000	100,128,000	94,483,000
Income per common share/unit - basic:
Continuing operations (in dollars per share)		$ 0.05	$ 0.57	$ 0.88	$ 1.18
Income per common share/unit - diluted:
Continuing operations (in dollars per share)		$ 0.05	$ 0.57	$ 0.88	$ 1.18
Partnership Interest [Member]
Earnings Per Share [Abstract]
Income from operations		$ 1,534	$ 31,979	$ 82,337	$ 94,789
Gain on sale of real estate, net of tax				$ 22,997	$ 34,215
Weighted average common units outstanding for basic EPU (in shares)		103,829,000	94,312,000	99,793,000	94,234,000
Weighted average common units outstanding for diluted EPU (in shares)		104,409,000	94,749,000	100,282,000	94,637,000
Income per common unit - basic
Continuing operations (in dollars per share)		$ 0.05	$ 0.57	$ 0.88	$ 1.18
Income per common unit - diluted
Continuing operations (in dollars per share)		$ 0.05	$ 0.57	$ 0.88	$ 1.18
Continuing Operations [Member] | Parent Company [Member]
Earnings Per Share [Abstract]
Net income attributable to common stockholders		$ 5,305	$ 53,731	$ 87,992	$ 111,384
Net income for common stock unit/holders - diluted		5,305	53,731	87,992	111,384
Continuing Operations [Member] | Partnership Interest [Member]
Earnings Per Share [Abstract]
Net income attributable to common stockholders		5,321	53,825	88,157	111,588
Net income for common stock unit/holders - diluted		$ 5,321	$ 53,825	$ 88,157	$ 111,588
Equity Offering [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Stock Issued During Period, Shares, New Issues	5,000,000