Components of income before income taxes from continuing operations (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
United States	$ 466,651	$ 474,856	$ 398,532
Foreign	0	261	(87)
Income before income taxes	$ 466,651	$ 475,117	$ 398,445

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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+ Details