The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Derivative Financial Instruments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Derivative [Line Items]
Gains reported in accumulated other comprehensive income			$ 1.1
Gain to be reclassified within next 12 months			1.1
Cash Flow Hedging \| Designated as Hedging Instrument \| Foreign currency forward contracts
Derivative [Line Items]
Derivatives, net gain (loss) reclassified into cost of services	$ 0.4	$ (0.3)	0.5	$ (0.4)
Notional amount	$ 26.2		$ 26.2		$ 52.0