Income Taxes - Unrecognized Tax Benefits (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Income Taxes
Amount of unrecognized tax benefits which, if recognized, would affect the effective tax rate	$ 4.6
Reconciliation of the beginning and ending amount of unrecognized tax benefits
Balance at the beginning of the period	10.2
Increases related to prior year tax positions	0.6
Decreases due to lapse in statutes	(1.3)
Currency movement	(0.2)
Balance at the end of the period	9.3
Decrease in unrecognized tax benefits, that is reasonably possible	$ 3.5

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from foreign currency translation.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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