CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets
Accumulated depreciation	$ 723,919	$ 681,657
Preferred stock, $0.01 par value; 10,000,000 shares authorized, zero shares issued and outstanding as of March 31, 2021 and December 31, 2020
Par value (in dollars per share)	$ 0.01	$ 0.01
Shares authorized (in shares)	10,000,000	10,000,000
Shares issued (in shares)	0	0
Shares outstanding (in shares)	0	0
Common stock, $0.01 par value; 500,000,000 shares authorized, 215,930,202 and 210,560,815 shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively
Par value (in dollars per share)	$ 0.01	$ 0.01
Shares authorized (in shares)	500,000,000	500,000,000
Shares issued (in shares)	215,930,202	210,560,815
Shares outstanding (in shares)	215,930,202	210,560,815