Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Discontinued operations, tax benefit (expense)	$ (3,942)	$ 3,765	$ 13,292	$ 42,618
Gain on sales of discontinued operations, tax expense (benefit)	$ 34,357	$ 0	$ 34,744	$ 20,792

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

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