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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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- Definition

Amount of financing receivable originated five or more years prior to latest fiscal year.

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Amount of financing receivable originated four years prior to latest fiscal year.

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Amount of financing receivable originated in current fiscal year.

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Amount of financing receivable originated in fiscal year prior to latest fiscal year.

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Amount of financing receivable originated three years prior to latest fiscal year.

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Amount of financing receivable originated two years prior to latest fiscal year.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Amount, before allowance for credit loss, of financing receivable.

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Mortgage Loans, Sorted by Applicable Credit Quality Indicators (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	$ 2,452.1		$ 2,397.0
Loan to Value Ratio Below or Equal to 65 Percent
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	1,244.4		1,215.1
Loan To Value Ratio Above 65 To 75 Percent
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	1,093.5		1,053.0
Loan To Value Ratio Above 75 To 85 Percent
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	40.5		91.4
Loan To Value Ratio Above 85 Percent
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	73.7		37.5
Originated Five or More Years before Last Fiscal Year
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	840.9
Originated Four Years before Last Fiscal Year
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	411.2
Originated Three Years before Last Fiscal Year
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	336.4
Originated Two Years before Last Fiscal Year
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	394.7
Originated in Fiscal Year before Latest Fiscal Year
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	371.9
Originated in Current Fiscal Year
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	97.0
Commercial Real Estate
Mortgage Loans on Real Estate
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	843.2
Financing Receivable, Originated Four Years before Latest Fiscal Year	413.0
Financing Receivable, Originated Three Years before Latest Fiscal Year	338.1
Financing Receivable, Originated Two Years before Latest Fiscal Year	397.1
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	374.2
Financing Receivable, Originated in Current Fiscal Year	97.6
Financing Receivable, before Allowance for Credit Loss	2,463.2		2,397.0
Financing Receivable, Allowance for Credit Losses, Mortgage Loans	11.1	$ 8.3
Commercial Real Estate \| Loan to Value Ratio Below or Equal to 65 Percent
Mortgage Loans on Real Estate
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	695.6
Financing Receivable, Originated Four Years before Latest Fiscal Year	241.5
Financing Receivable, Originated Three Years before Latest Fiscal Year	119.1
Financing Receivable, Originated Two Years before Latest Fiscal Year	78.4
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	84.3
Financing Receivable, Originated in Current Fiscal Year	29.0
Financing Receivable, before Allowance for Credit Loss	1,247.9
Financing Receivable, Allowance for Credit Losses, Mortgage Loans	3.5	2.8
Commercial Real Estate \| Loan To Value Ratio Above 65 To 75 Percent
Mortgage Loans on Real Estate
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	69.5
Financing Receivable, Originated Four Years before Latest Fiscal Year	134.4
Financing Receivable, Originated Three Years before Latest Fiscal Year	219.0
Financing Receivable, Originated Two Years before Latest Fiscal Year	318.7
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	289.9
Financing Receivable, Originated in Current Fiscal Year	68.6
Financing Receivable, before Allowance for Credit Loss	1,100.1
Financing Receivable, Allowance for Credit Losses, Mortgage Loans	6.5	4.6
Commercial Real Estate \| Loan To Value Ratio Above 75 To 85 Percent
Mortgage Loans on Real Estate
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	3.7
Financing Receivable, Originated Four Years before Latest Fiscal Year	37.1
Financing Receivable, Originated Three Years before Latest Fiscal Year	0.0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0.0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0.0
Financing Receivable, Originated in Current Fiscal Year	0.0
Financing Receivable, before Allowance for Credit Loss	40.8
Financing Receivable, Allowance for Credit Losses, Mortgage Loans	0.4	0.5
Commercial Real Estate \| Loan To Value Ratio Above 85 Percent
Mortgage Loans on Real Estate
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	74.4
Financing Receivable, Originated Four Years before Latest Fiscal Year	0.0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0.0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0.0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0.0
Financing Receivable, Originated in Current Fiscal Year	0.0
Financing Receivable, before Allowance for Credit Loss	74.4
Financing Receivable, Allowance for Credit Losses, Mortgage Loans	0.7	$ 0.4
Commercial Real Estate \| Originated Five or More Years before Last Fiscal Year
Mortgage Loans on Real Estate
Financing Receivable, Allowance for Credit Losses, Mortgage Loans	2.3
Commercial Real Estate \| Originated Four Years before Last Fiscal Year
Mortgage Loans on Real Estate
Financing Receivable, Allowance for Credit Losses, Mortgage Loans	1.8
Commercial Real Estate \| Originated Three Years before Last Fiscal Year
Mortgage Loans on Real Estate
Financing Receivable, Allowance for Credit Losses, Mortgage Loans	1.7
Commercial Real Estate \| Originated Two Years before Last Fiscal Year
Mortgage Loans on Real Estate
Financing Receivable, Allowance for Credit Losses, Mortgage Loans	2.4
Commercial Real Estate \| Originated in Fiscal Year before Latest Fiscal Year
Mortgage Loans on Real Estate
Financing Receivable, Allowance for Credit Losses, Mortgage Loans	2.3
Commercial Real Estate \| Originated in Current Fiscal Year
Mortgage Loans on Real Estate
Financing Receivable, Allowance for Credit Losses, Mortgage Loans	0.6
A Credit Rating
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	485.7		485.6
A Credit Rating \| Commercial Real Estate
Mortgage Loans on Real Estate
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	236.7
Financing Receivable, Originated Four Years before Latest Fiscal Year	119.0
Financing Receivable, Originated Three Years before Latest Fiscal Year	53.1
Financing Receivable, Originated Two Years before Latest Fiscal Year	60.4
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	17.6
Financing Receivable, Originated in Current Fiscal Year	0.0
Financing Receivable, before Allowance for Credit Loss	486.8
BBB Credit Rating
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	1,919.6		1,911.4
BBB Credit Rating \| Commercial Real Estate
Mortgage Loans on Real Estate
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	559.7
Financing Receivable, Originated Four Years before Latest Fiscal Year	294.0
Financing Receivable, Originated Three Years before Latest Fiscal Year	285.0
Financing Receivable, Originated Two Years before Latest Fiscal Year	336.7
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	356.6
Financing Receivable, Originated in Current Fiscal Year	97.6
Financing Receivable, before Allowance for Credit Loss	1,929.6
BB Credit Rating
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	30.0		0.0
BB Credit Rating \| Commercial Real Estate
Mortgage Loans on Real Estate
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	30.0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0.0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0.0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0.0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0.0
Financing Receivable, Originated in Current Fiscal Year	0.0
Financing Receivable, before Allowance for Credit Loss	30.0
B Credit Rating
Mortgage Loans on Real Estate
Mortgage Loans, Carrying Amount	16.8		$ 0.0
B Credit Rating \| Commercial Real Estate
Mortgage Loans on Real Estate
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	16.8
Financing Receivable, Originated Four Years before Latest Fiscal Year	0.0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0.0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0.0
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year	0.0
Financing Receivable, Originated in Current Fiscal Year	0.0
Financing Receivable, before Allowance for Credit Loss	$ 16.8