Consolidated Statements of Operations (Parenthetical) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Income from discontinued operations, tax	$ 17,539,000	$ 48,771,000	$ 26,176,000
Tax from gain on sales of discontinued operations	$ 33,472,000	$ 3,466,000	$ 0

Amount of tax expense (benefit) on gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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