Other Assets and Receivables (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Investment in Qualified Affordable Housing Limited Partnerships
Investments for qualified affordable housing limited partnerships	$ 73.0	$ 31.5
Additional contribution on qualified affordable housing limited partnerships	36.8	24.4
Amortization expense	2.1	2.0	$ 1.8
Tax credit	2.1	2.0	$ 2.0
Joint Ventures
Investments in debt funds	29.8	25.6
Additional investment in joint ventures	3.5	10.4
Other Receivables
Other receivables	10.5	11.7
Short term receivables	6.0	6.5
Accrued fees	2.2	0.0
Other receivables, collateral recorded against outstanding hedges	0.0	3.9
Corporate Joint Venture [Member]
Joint Ventures
Investment in joint ventures	$ 37.5	$ 31.0

The amount of additional investment expected in future period as at the end of the reporting period.

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The amount of investment in debt funds as at the end of the reporting period.

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The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.

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For an unclassified balance sheet, the amount of fees and other revenue, excluding investment income receivable, earned but not yet received, which were recognized in conformity with revenue recognition criteria based on estimates or specific contractual terms.

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Amount of investment in qualified affordable housing projects.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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The amount deducted from an entities' taxes, reflecting a percentage of an amount invested in certain assets spread over the useful life of those assets; includes deferred investment tax credits.

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Amount due from parties in nontrade transactions, classified as other.

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Amount, after allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

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Amount of commitment or contingent commitments to qualified affordable housing project investments.

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Fair value of the securities pledged as collateral against securities loaned.

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