Fair Value - Inputs (Details) $ in Millions	4 Months Ended	9 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2018 USD ($)
Fair Value
Estimated fair value of Visa preferred shares	$ 28.4	$ 28.4
Maximum | Growth Rate
Fair Value
Redeemable non-controlling interest, measurement input (as a percent)		25.60%
eService | Weighted Average Cost of Capital
Fair Value
Redeemable non-controlling interest, measurement input (as a percent)		17.50%
eService | Minimum | Growth Rate
Fair Value
Redeemable non-controlling interest, measurement input (as a percent)		3.00%
Blueapple | Discount for lack of marketability
Fair Value
Redeemable non-controlling interest, measurement input (as a percent)	5.00%
Put option exercise period	6 months