Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands									7 Months Ended	12 Months Ended		19 Months Ended
	Dec. 03, 2019	Nov. 29, 2019	Nov. 22, 2019	Nov. 14, 2019	Oct. 22, 2019	Sep. 12, 2019	Jul. 26, 2019	Jul. 23, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 02, 2019	Jul. 22, 2019	Feb. 28, 2019	Jun. 13, 2018	Dec. 31, 2017
Subsidiary, Sale of Stock [Line Items]
Preferred Stock, Shares Issued					4,600,000					4,600,000		4,600,000
Proceeds from Issuance of Preferred Stock and Preference Stock					$ 111,000					$ 111,378
Preferred Stock, Dividend Rate, Percentage					6.75%					6.75%
Preferred Stock, Shares Outstanding										4,600,000		4,600,000
Preferred Stock, Shares Authorized										100,000,000		100,000,000
Preferred Stock, Par or Stated Value Per Share					$ 0.001					$ 0.001		$ 0.001
Preferred Stock, Liquidation Preference Per Share										$ 25.00		$ 25.00
Preferred Stock, Amount of Preferred Dividends in Arrears										$ 1,500
Preferred Stock Dividend Rate Variable Rate Spread										5.196%
Common stock, shares authorized (in shares)									100,000,000	100,000,000	100,000,000	100,000,000
Common shares										$ 0.001		$ 0.001			$ 0.001
Common stock, shares outstanding									29,796,601	38,647,943	29,796,601	38,647,943					31,335,938
Dividends declared (in usd per share)										$ 1.81	$ 1.64
Dividends paid										$ (54,312)	$ (50,736)
Common shares issued and outstanding upon conversion of all convertible securities (in shares)									30,529,972	39,371,584	30,529,972	39,371,584
Number of shares authorized to be repurchased (in shares)																1,550,000
Shares repurchased (in shares)									361,090	50,825	1,547,148	411,915
Average price per share (USD per share)									$ 15.34	$ 15.39	$ 14.95	$ 15.34
Total cost									$ (5,500)	$ (782)	$ (23,131)	$ (6,300)
Stock Issued During Period, Shares, New Issues	630,000		4,200,000				525,000	3,500,000		8,855,000
Proceeds from issuance of shares, net			$ 75,300				$ 9,100						$ 11,200	$ 60,700
Stock issued during period, shares, conversion of units											3,334
Over-Allotment Option [Member]
Subsidiary, Sale of Stock [Line Items]
Preferred Stock, Shares Issued					600,000
OP LTIP Unit [Member]
Subsidiary, Sale of Stock [Line Items]
Stock issued during period, shares, conversion of units		1,874		7,608		3,610				13,092
Operating Partnership Units [Member]
Subsidiary, Sale of Stock [Line Items]
Stock issued during period, shares, conversion of units		4,313		29,762						34,075