Income Taxes - Deferred Tax Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Deferred Tax Liabilities:
Lease Financing	$ 43.3	$ 85.8
Software Development	193.2	187.8
Accumulated Depreciation	129.5	41.0
Compensation and Benefits	10.9	0.0
State Taxes, net	58.9	59.4
Other Liabilities	114.5	145.7
Gross Deferred Tax Liabilities	550.3	519.7
Deferred Tax Assets:
Allowance for Credit Losses	29.0	32.3
Compensation and Benefits	0.0	35.5
Other Assets	120.6	88.3
Gross Deferred Tax Assets	149.6	156.1
Valuation Reserve	(0.3)	(1.1)
Deferred Tax Assets, net of Valuation Reserve	149.3	155.0
Net Deferred Tax Liabilities	$ 401.0	$ 364.7