Other Assets - Affordable Housing and Other Tax Credit Investment Partnerships (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Affordable housing and other tax credit investment partnership interests
Affordable housing tax credits and other benefits recognized	$ 10.6	$ 6.3	$ 4.5
Provision for income taxes
Affordable housing and other tax credit investment partnership interests
Amortization	11.3	5.2	$ 3.5
Included in other assets
Affordable housing and other tax credit investment partnership interests
Investment partnership interest	$ 145.6	$ 111.5

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-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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