Condensed Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Cumulative Distributions in Excess of Earnings
Beginning balance at Dec. 31, 2018	$ 768,247	$ 859	$ 965,578	$ (198,190)
Beginning balance (in shares) at Dec. 31, 2018		85,867,044
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock, net	47,243	$ 24	47,219
Issuance of common stock, net, (in shares)		2,459,000
Vesting of restricted common stock, net of shares withheld for employee taxes	(1,495)	$ 1	(1,496)
Vesting of restricted common stock, net of shares withheld for employee taxes (in shares)		72,229
Amortization of stock-based compensation	994		994
Common dividends	(20,011)			(20,011)
Net income	16,053			16,053
Ending balance at Mar. 31, 2019	811,031	$ 884	1,012,295	(202,148)
Ending balance (in shares) at Mar. 31, 2019		88,398,273
Beginning balance at Dec. 31, 2018	768,247	$ 859	965,578	(198,190)
Beginning balance (in shares) at Dec. 31, 2018		85,867,044
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	25,697
Ending balance at Sep. 30, 2019	927,486	$ 951	1,162,047	(235,512)
Ending balance (in shares) at Sep. 30, 2019		95,103,270
Beginning balance at Mar. 31, 2019	811,031	$ 884	1,012,295	(202,148)
Beginning balance (in shares) at Mar. 31, 2019		88,398,273
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock, net	148,798	$ 67	148,731
Issuance of common stock, net, (in shares)		6,641,250
Vesting of restricted common stock, net of shares withheld for employee taxes	(1,029)		(1,029)
Vesting of restricted common stock, net of shares withheld for employee taxes (in shares)		33,700
Amortization of stock-based compensation	1,147		1,147
Common dividends	(21,508)			(21,508)
Net income	19,698			19,698
Ending balance at Jun. 30, 2019	958,137	$ 951	1,161,144	(203,958)
Ending balance (in shares) at Jun. 30, 2019		95,073,223
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock, net	(78)		(78)
Vesting of restricted common stock, net of shares withheld for employee taxes	0
Vesting of restricted common stock, net of shares withheld for employee taxes (in shares)		30,047
Amortization of stock-based compensation	981		981
Common dividends	(21,500)			(21,500)
Net income	(10,054)			(10,054)
Ending balance at Sep. 30, 2019	927,486	$ 951	1,162,047	(235,512)
Ending balance (in shares) at Sep. 30, 2019		95,103,270
Beginning balance at Dec. 31, 2019	927,591	$ 951	1,162,990	(236,350)
Beginning balance (in shares) at Dec. 31, 2019		95,103,270
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock, net	(90)		(90)
Vesting of restricted common stock, net of shares withheld for employee taxes	(1,986)	$ 1	(1,987)
Vesting of restricted common stock, net of shares withheld for employee taxes (in shares)		93,061
Amortization of stock-based compensation	884		884
Common dividends	(23,931)			(23,931)
Net income	19,325			19,325
Ending balance at Mar. 31, 2020	921,793	$ 952	1,161,797	(240,956)
Ending balance (in shares) at Mar. 31, 2020		95,196,331
Beginning balance at Dec. 31, 2019	927,591	$ 951	1,162,990	(236,350)
Beginning balance (in shares) at Dec. 31, 2019		95,103,270
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	59,812
Ending balance at Sep. 30, 2020	916,036	$ 952	1,163,418	(248,334)
Ending balance (in shares) at Sep. 30, 2020		95,214,080
Beginning balance at Mar. 31, 2020	921,793	$ 952	1,161,797	(240,956)
Beginning balance (in shares) at Mar. 31, 2020		95,196,331
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock, net	(314)		(314)
Vesting of restricted common stock, net of shares withheld for employee taxes	0	$ 0	0
Vesting of restricted common stock, net of shares withheld for employee taxes (in shares)		17,749
Amortization of stock-based compensation	963		963
Common dividends	(23,931)			(23,931)
Net income	18,935			18,935
Ending balance at Jun. 30, 2020	917,446	$ 952	1,162,446	(245,952)
Ending balance (in shares) at Jun. 30, 2020		95,214,080
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Amortization of stock-based compensation	972		972
Common dividends	(23,934)			(23,934)
Net income	21,552			21,552
Ending balance at Sep. 30, 2020	$ 916,036	$ 952	$ 1,163,418	$ (248,334)
Ending balance (in shares) at Sep. 30, 2020		95,214,080