CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Property and equipment, accumulated depreciation	$ 4,368,659	$ 3,969,566
Intangible assets, accumulated amortization	$ 75,727	$ 81,922
Preferred stock, par value (usd per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, issued (in shares)	0	0
Common stock, par value (usd per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	450,000,000	450,000,000
Common stock, shares issued (in shares)	126,065,294	125,842,853
Common stock, shares outstanding (in shares)	113,781,317	125,842,853
Treasury Stock, Common, Shares	12,283,977	0