Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Net number of share options (or share units) granted during the period.

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Value, after forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Amount of stockholders' equity including the portion attributable to noncontrolling interests, after the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Shares	Additional Paid-in Capital	Cumulative Net Income	Cumulative Other Comprehensive Income (Loss)	Cumulative Distributions	Total Equity Attributable to Common Shareholders	Total Equity Attributable to Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative adjustment upon adoption of ASU No. 2016-01	$ 0			$ 87,429	$ (87,429)
Adjusted balance	3,277,188	$ 2,376	$ 4,609,316	1,853,924	(198)	$ (3,360,468)	$ 3,104,950	$ 172,238
Beginning balance (in shares) at Dec. 31, 2017		237,630,409
Beginning balance at Dec. 31, 2017	3,277,188	$ 2,376	4,609,316	1,766,495	87,231	(3,360,468)	3,104,950	172,238
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	237,405			236,022			236,022	1,383
Other comprehensive income (loss)	(93)				(93)		(93)
Distributions	(92,674)					(92,674)	(92,674)
Share grants (in shares)		3,000
Share grants	47		47				47
Share repurchases (in shares)		(4,628)
Share repurchases	(89)		(89)				(89)
Distributions to noncontrolling interest	(5,667)							(5,667)
Ending balance (in shares) at Mar. 31, 2018		237,628,781
Ending balance at Mar. 31, 2018	3,416,117	$ 2,376	4,609,274	2,089,946	(291)	(3,453,142)	3,248,163	167,954
Beginning balance (in shares) at Dec. 31, 2017		237,630,409
Beginning balance at Dec. 31, 2017	3,277,188	$ 2,376	4,609,316	1,766,495	87,231	(3,360,468)	3,104,950	172,238
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	409,596
Other comprehensive income (loss)	90
Ending balance (in shares) at Sep. 30, 2018		237,730,900
Ending balance at Sep. 30, 2018	3,394,480	$ 2,377	4,610,885	2,259,338	(108)	(3,638,499)	3,233,993	160,487
Beginning balance (in shares) at Mar. 31, 2018		237,628,781
Beginning balance at Mar. 31, 2018	3,416,117	$ 2,376	4,609,274	2,089,946	(291)	(3,453,142)	3,248,163	167,954
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	124,988			123,587			123,587	1,401
Other comprehensive income (loss)	10				10		10
Distributions	(92,676)					(92,676)	(92,676)
Share grants (in shares)		15,000
Share grants	248		248				248
Distributions to noncontrolling interest	(5,114)							(5,114)
Ending balance (in shares) at Jun. 30, 2018		237,643,781
Ending balance at Jun. 30, 2018	3,443,573	$ 2,376	4,609,522	2,213,533	(281)	(3,545,818)	3,279,332	164,241
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	47,202			45,805			45,805	1,397
Other comprehensive income (loss)	173				173		173
Distributions	(92,681)					(92,681)	(92,681)
Share grants (in shares)		105,800
Share grants	1,679	$ 1	1,678				1,679
Share repurchases (in shares)		(18,681)
Share repurchases	(315)		(315)				(315)
Distributions to noncontrolling interest	(5,151)							(5,151)
Ending balance (in shares) at Sep. 30, 2018		237,730,900
Ending balance at Sep. 30, 2018	$ 3,394,480	$ 2,377	4,610,885	2,259,338	(108)	(3,638,499)	3,233,993	160,487
Beginning balance (in shares) at Dec. 31, 2018	237,729,900	237,729,900
Beginning balance at Dec. 31, 2018	$ 3,179,870	$ 2,377	4,611,419	2,140,796	(266)	(3,731,214)	3,023,112	156,758
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	31,504			30,082			30,082	1,422
Other comprehensive income (loss)	66				66		66
Distributions	(92,714)					(92,714)	(92,714)
Share grants	215		215				215
Distributions to noncontrolling interest	(5,503)							(5,503)
Ending balance (in shares) at Mar. 31, 2019		237,729,900
Ending balance at Mar. 31, 2019	$ 3,113,438	$ 2,377	4,611,634	2,170,878	(200)	(3,823,928)	2,960,761	152,677
Beginning balance (in shares) at Dec. 31, 2018	237,729,900	237,729,900
Beginning balance at Dec. 31, 2018	$ 3,179,870	$ 2,377	4,611,419	2,140,796	(266)	(3,731,214)	3,023,112	156,758
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(32,258)
Other comprehensive income (loss)	$ 91
Ending balance (in shares) at Sep. 30, 2019	237,900,277	237,900,277
Ending balance at Sep. 30, 2019	$ 2,968,222	$ 2,379	4,612,264	2,104,259	(175)	(3,895,248)	2,823,479	144,743
Beginning balance (in shares) at Mar. 31, 2019		237,729,900
Beginning balance at Mar. 31, 2019	3,113,438	$ 2,377	4,611,634	2,170,878	(200)	(3,823,928)	2,960,761	152,677
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(35,816)			(37,229)			(37,229)	1,413
Other comprehensive income (loss)	71				71		71
Distributions	(35,659)					(35,659)	(35,659)
Share grants (in shares)		15,000
Share grants	395		395				395
Share repurchases (in shares)		(4,139)
Share repurchases	(36)		(36)				(36)
Distributions to noncontrolling interest	(5,684)							(5,684)
Ending balance (in shares) at Jun. 30, 2019		237,740,761
Ending balance at Jun. 30, 2019	3,036,709	$ 2,377	4,611,993	2,133,649	(129)	(3,859,587)	2,888,303	148,406
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(27,946)			(29,390)			(29,390)	1,444
Other comprehensive income (loss)	(46)				(46)		(46)
Distributions	(35,661)					(35,661)	(35,661)
Share grants (in shares)		187,500
Share grants	532	$ 2	530				532
Share repurchases (in shares)		(27,984)
Share repurchases	(259)		(259)				(259)
Distributions to noncontrolling interest	$ (5,107)							(5,107)
Ending balance (in shares) at Sep. 30, 2019	237,900,277	237,900,277
Ending balance at Sep. 30, 2019	$ 2,968,222	$ 2,379	$ 4,612,264	$ 2,104,259	$ (175)	$ (3,895,248)	$ 2,823,479	$ 144,743