Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Income before income taxes	$ 189,389			$ 142,267	$ 90,311	$ 333,125
Provision for (benefit from) income taxes	$ 20,865			$ 8,545	$ (67,482)	$ 13,757
Effective tax rate	11.00%			6.00%	(74.70%)	4.10%
Legal settlement charge	$ 0	$ 405,000		$ 0	$ 405,000	$ 0
Provisional income tax expense			$ 51,800

Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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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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Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

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