Income Taxes - Deferred Tax Liabilities (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Deferred Tax Liabilities:
Lease Financing	$ 7.0	$ 9.0
Software Development	271.8	268.1
Depreciation and Amortization	181.3	147.0
Unrealized Gains on Securities, net	82.8	247.6
Compensation and Benefits	65.6	43.8
State Taxes, net	76.3	67.4
Other Liabilities	23.3	18.7
Gross Deferred Tax Liabilities	708.1	801.6
Deferred Tax Assets:
Allowance for Credit Losses	38.6	54.5
Tax Credit and Loss Carryforwards	68.2	55.2
Other Assets	85.4	38.4
Gross Deferred Tax Assets	192.2	148.1
Valuation Reserve	(68.2)	(55.2)
Deferred Tax Assets, net of Valuation Reserve	124.0	92.9
Net Deferred Tax Liabilities	$ 584.1	$ 708.7