Common Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		12 Months Ended
	Sep. 30, 2019	Feb. 28, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shelf registration, shares issued (in shares)	7,000,000
Shelf registration, price per share (in dollars per share)	$ 56.50
Shelf registration, net proceeds	$ 379,410
Stock issuance costs	$ 16,090		$ 2,223	$ 17,521	$ 3,947
Total allowable shares (in shares)			375,000,000	375,000,000
Total shares issued (in shares)			175,232,971	171,694,209
Shares of common stock (in shares)				7,000,000
Net proceeds				$ 395,500
Net proceeds			$ 126,488	542,280	345,324
2020 ATM Equity Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total allowable shares (in shares)			17,500,000
Total shares issued (in shares)			1,569,304
2018 ATM Equity Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total allowable shares (in shares)			12,000,000
Total shares issued (in shares)			11,272,034
ATM Equity Programs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issuance costs			$ 2,130	$ 1,431	$ 3,821
Shares of common stock (in shares)			3,119,153	2,344,022	7,378,163
Average price per share (net) (in dollars per share)			$ 38.21	$ 53.71	$ 44.48
Net proceeds			$ 119,185	$ 125,905	$ 328,196
DRIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares permitted for issuance (in shares)		10,000,000
Shares of common stock (in shares)			138,507	362,918	311,048
Net proceeds			$ 5,092	$ 19,442	$ 13,264