Derivative Financial Instruments Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair value of derivative assets and liabilities
Derivative, fair value, net	$ (405,000)	$ (168,200)
Derivative assets, current	20,859	31,203
Derivative assets, noncurrent	13,567	23,150
Total derivative assets	34,426	54,353
Derivative liabilities, current	371,802	200,189
Derivatives liabilities, noncurrent	67,595	22,331
Total derivative liabilities	(439,397)	(222,520)
Derivative asset, amounts not offset in the accompanying balance sheets	(34,238)	(53,598)
Derivative liabilities, amounts not offset in the accompanying balance sheets	34,238	53,598
Derivative asset, fair value, net amounts	188	755
Derivative liabilities, fair value, net amounts	(405,159)	(168,922)
Not Designated as Hedging Instrument [Member]
Fair value of derivative assets and liabilities
Derivative assets, current	20,859	31,203
Derivative assets, noncurrent	13,567	23,150
Derivative liabilities, current	371,802	200,189
Derivatives liabilities, noncurrent	67,595	22,331
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Not Designated as Hedging Instrument [Member]
Fair value of derivative assets and liabilities
Total derivative assets	34,426	54,353
Total derivative liabilities	$ 439,397	$ 222,520