The numbers of days for which a mortgage loan has been delinquent such that it is considered non-performing.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 55
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-Topic 326
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- Definition

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

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- Definition

Amount of financing receivable originated in current fiscal year.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
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- Definition

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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

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-Publisher FASB
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-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

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

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-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
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- Definition

Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

+ References

No definition available.

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Investments - Mortgage Loan Credit Monitoring (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost	$ 17,389.7	$ 16,513.9	$ 16,164.9
Reinsurance recoverables	1,076.0
Accrued interest receivable	548.8
Commercial mortgage loans
Financing Receivable, Credit Quality Indicator
2020	917.0
2019	2,790.7
2018	2,821.1
2017	2,090.6
2016	1,644.8
Prior	4,831.3
Mortgage loans, Total amortized cost	15,095.5	15,017.2	14,830.6
Accrued interest receivable	58.8
Commercial mortgage loans \| A- and above
Financing Receivable, Credit Quality Indicator
2020	807.2
2019	2,543.9
2018	2,478.7
2017	1,803.8
2016	1,538.5
Prior	4,213.4
Mortgage loans, Total amortized cost	13,385.5	13,961.9
Commercial mortgage loans \| BBB+ thru BBB-
Financing Receivable, Credit Quality Indicator
2020	95.0
2019	205.7
2018	342.4
2017	286.8
2016	89.4
Prior	538.8
Mortgage loans, Total amortized cost	1,558.1	1,026.9
Commercial mortgage loans \| BB+ thru BB-
Financing Receivable, Credit Quality Indicator
2020	14.8
2019	41.1
2016	16.9
Prior	74.5
Mortgage loans, Total amortized cost	147.3	23.3
Commercial mortgage loans \| B+ and below
Financing Receivable, Credit Quality Indicator
Prior	4.6
Mortgage loans, Total amortized cost	4.6	5.1
Brick and mortar
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		14,856.7
Brick and mortar \| A- and above
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		13,885.2
Brick and mortar \| BBB+ thru BBB-
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		943.1
Brick and mortar \| BB+ thru BB-
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		23.3
Brick and mortar \| B+ and below
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		5.1
Credit tenant loans
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		160.5
Credit tenant loans \| A- and above
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		76.7
Credit tenant loans \| BBB+ thru BBB-
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		83.8
Direct financing leases
Financing Receivable, Credit Quality Indicator
2020	148.6
2019	25.7
2018	60.5
2017	36.1
2016	16.8
Prior	359.4
Mortgage loans, Total amortized cost	647.1
Direct financing leases \| A- and above
Financing Receivable, Credit Quality Indicator
2020	41.0
2019	1.5
2018	36.9
2017	16.6
2016	13.3
Prior	205.3
Mortgage loans, Total amortized cost	314.6
Direct financing leases \| BBB+ thru BBB-
Financing Receivable, Credit Quality Indicator
2020	95.2
2019	22.4
2018	20.0
2017	19.5
2016	3.5
Prior	149.9
Mortgage loans, Total amortized cost	310.5
Direct financing leases \| BB+ thru BB-
Financing Receivable, Credit Quality Indicator
2020	11.0
2019	1.8
2018	3.6
Prior	4.2
Mortgage loans, Total amortized cost	20.6
Direct financing leases \| B+ and below
Financing Receivable, Credit Quality Indicator
2020	1.4
Mortgage loans, Total amortized cost	1.4
Residential mortgage loans
Financing Receivable, Credit Quality Indicator
2020	243.5
2019	461.6
2018	193.5
2017	180.9
2016	171.1
Prior	396.5
Mortgage loans, Total amortized cost	1,647.1	1,496.7	$ 1,334.3
Residential mortgage loans \| Performing
Financing Receivable, Credit Quality Indicator
2020	243.5
2019	460.7
2018	192.6
2017	180.8
2016	171.1
Prior	389.1
Mortgage loans, Total amortized cost	1,637.8	1,482.2
Residential mortgage loans \| Non-performing
Financing Receivable, Credit Quality Indicator
2019	0.9
2018	0.9
2017	0.1
Prior	7.4
Mortgage loans, Total amortized cost	$ 9.3	14.5
Mortgage loans, Days delinquent to be considered non-performing	90 days
First liens
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		1,485.7
First liens \| Performing
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		1,474.2
First liens \| Non-performing
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		11.5
Home equity
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		11.0
Home equity \| Performing
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		8.0
Home equity \| Non-performing
Financing Receivable, Credit Quality Indicator
Mortgage loans, Total amortized cost		$ 3.0