Recorded investment in financing receivables that are 90 days or more past due and still accruing.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5111-111524

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- Definition

Financing receivables that are current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953401-111524

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(3))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Investments - Non-Accrual Mortgage Loans (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Mortgage loan non-accrual and aging disclosures
Mortgage loans, Non-accrual status	$ 18.7	$ 33.4
Past due	39.6	55.4
Current	12,351.4	11,812.7
Mortgage loans, Total amortized cost	12,391.0	11,868.1	$ 11,603.4
Recorded investment 90 days or more past due and accruing	3.4	4.5
30 to 59 Days Past Due
Mortgage loan non-accrual and aging disclosures
Past due	22.5	26.5
60 to 89 Days Past Due
Mortgage loan non-accrual and aging disclosures
Past due	6.5	12.7
90 Days or More Past Due
Mortgage loan non-accrual and aging disclosures
Past due	10.6	16.2
Commercial mortgage loans
Mortgage loan non-accrual and aging disclosures
Mortgage loans, Total amortized cost	11,265.3	10,723.8	10,327.7
Brick and mortar
Mortgage loan non-accrual and aging disclosures
Mortgage loans, Non-accrual status		9.6
Past due		5.2
Current	10,921.0	10,369.7
Mortgage loans, Total amortized cost	10,921.0	10,374.9
Brick and mortar \| 60 to 89 Days Past Due
Mortgage loan non-accrual and aging disclosures
Past due		4.5
Brick and mortar \| 90 Days or More Past Due
Mortgage loan non-accrual and aging disclosures
Past due		0.7
Credit tenant loans
Mortgage loan non-accrual and aging disclosures
Current	344.3	348.9
Mortgage loans, Total amortized cost	344.3	348.9
Residential mortgage loans
Mortgage loan non-accrual and aging disclosures
Mortgage loans, Total amortized cost	1,125.7	1,144.3	$ 1,275.7
Home equity
Mortgage loan non-accrual and aging disclosures
Mortgage loans, Non-accrual status	10.8	15.0
Past due	3.6	6.9
Current	215.2	276.5
Mortgage loans, Total amortized cost	218.8	283.4
Home equity \| 30 to 59 Days Past Due
Mortgage loan non-accrual and aging disclosures
Past due	2.0	2.3
Home equity \| 60 to 89 Days Past Due
Mortgage loan non-accrual and aging disclosures
Past due	1.0	1.2
Home equity \| 90 Days or More Past Due
Mortgage loan non-accrual and aging disclosures
Past due	0.6	3.4
First liens
Mortgage loan non-accrual and aging disclosures
Mortgage loans, Non-accrual status	7.9	8.8
Past due	36.0	43.3
Current	870.9	817.6
Mortgage loans, Total amortized cost	906.9	860.9
Recorded investment 90 days or more past due and accruing	3.4	4.5
First liens \| 30 to 59 Days Past Due
Mortgage loan non-accrual and aging disclosures
Past due	20.5	24.2
First liens \| 60 to 89 Days Past Due
Mortgage loan non-accrual and aging disclosures
Past due	5.5	7.0
First liens \| 90 Days or More Past Due
Mortgage loan non-accrual and aging disclosures
Past due	$ 10.0	$ 12.1