Income Taxes - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Tax expense from discrete items	$ 1.4	$ 2.4
Adjustment for share-based compensation		$ 1.8
Federal statutory tax rate	21.00%
Probability threshold	50.00%
Unrecognized tax benefits	$ 19.0		$ 18.0

Unrecognized Tax Benefits, Including Foreign Tax Credits and Penalties and Interest

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- Definition

Unrecognized Tax Benefits, Probability Threshold of Realizing for Tax Benefits Recognition, Minimum Percentage

+ References

No definition available.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

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- Definition

Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible equity-based compensation costs.

+ References

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- Definition

Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

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