Distributions Paid and Payable - Distributions to Common Stockholders (Details) - $ / shares	1 Months Ended													6 Months Ended
	Jul. 31, 2020	Jun. 30, 2020	May 31, 2020	Apr. 30, 2020	Mar. 31, 2020	Feb. 29, 2020	Jan. 31, 2020	Jun. 30, 2019	May 31, 2019	Apr. 30, 2019	Mar. 31, 2019	Feb. 28, 2019	Jan. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Distributions Paid and Payable
Distributions paid per common share (in dollars per share)		$ 0.2330	$ 0.2330	$ 0.2330	$ 0.2325	$ 0.2325	$ 0.2275	$ 0.2260	$ 0.2260	$ 0.2260	$ 0.2255	$ 0.2255	$ 0.2210	$ 1.3915	$ 1.3500
Distributions payable (in dollars per share)		$ 0.2335												$ 0.2335
Subsequent event
Distributions Paid and Payable
Distributions paid per common share (in dollars per share)	$ 0.2335