Consolidated Statement of Operations (Parenthetical) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Income from discontinued operations, tax	$ 47,382,000	$ 24,495,000	$ 30,561,000
Tax from gain on sales of discontinued operations	$ 3,466	$ 0	$ 0

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

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