Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Discontinued operations, tax benefit (expense)	$ (9,350)	$ (46,382)
Gain on sales of discontinued operations, tax expense (benefit)	$ (287)	$ (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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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration