REVENUE - Contract Assets and Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Change in Contract with Customer, Liability
Deferred revenue	$ 851.9		$ 922.0
Cash proceeds	118.2
Revenue recognized	(117.8)
Effects of foreign currency translation	(70.5)
Amounts recognized in the consolidated balance sheets:
Deferred revenue (current)	748.3		807.9
Deferred revenue (non-current)	$ 103.6		114.1
Period for which interest and fee income accrue until balance, interest and fees paid or charged off	180 days
LoyaltyOne | Other current liabilities
Change in Contract with Customer, Liability
Deferred revenue	$ 79.0	$ 122.8
Revenue recognized	(89.6)
Service
Change in Contract with Customer, Liability
Deferred revenue	235.2		258.6
Cash proceeds	44.8
Revenue recognized	(48.6)
Effects of foreign currency translation	(19.6)
Amounts recognized in the consolidated balance sheets:
Deferred revenue (current)	131.6
Deferred revenue (non-current)	103.6
Redemption
Change in Contract with Customer, Liability
Deferred revenue	616.7		$ 663.4
Cash proceeds	73.4
Revenue recognized	(69.2)
Effects of foreign currency translation	(50.9)
Amounts recognized in the consolidated balance sheets:
Deferred revenue (current)	$ 616.7