Other Assets - Affordable Housing and Other Tax Credit Investment Partnerships (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Affordable housing and other tax credit investment partnership interests
Affordable housing tax credits and other benefits recognized	$ 26.9	$ 22.7	$ 15.8
Provision for income taxes
Affordable housing and other tax credit investment partnership interests
Amortization	24.4	21.7	$ 10.5
Included in other assets
Affordable housing and other tax credit investment partnership interests
Investment partnership interest	$ 167.4	$ 184.3

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

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-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
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Amount of investment in qualified affordable housing projects.

+ References

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

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