Other Assets - Affordable Housing and Other Tax Credit Investment Partnerships (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Affordable housing and other tax credit investment partnership interests
Affordable housing tax credits and other benefits recognized	$ 22.7	$ 15.8	$ 10.6
Provision for income taxes
Affordable housing and other tax credit investment partnership interests
Amortization	21.7	10.5	$ 11.3
Included in other assets
Affordable housing and other tax credit investment partnership interests
Investment partnership interest	$ 184.3	$ 170.2

Amount of affordable housing tax credits and other tax benefits recognized.

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Amount of investment in qualified affordable housing projects.

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Amount of amortization expense of investment in qualified affordable housing projects.

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