Available-for-sale Securities, Continuous Unrealized Losses, Twelve Months or Longer.

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- Definition

Below Investment Grade Securities, Gross Unrealized Losses

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- Definition

Commercial Mortgage Loan,Concentration Percentage

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- Definition

Commercial mortgage loans, transferred to affiliates

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- Definition

Investment Grade Securities, Gross Unrealized Losses

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- Definition

Securities, Continuous Unrealized Loss Position, declines in value of greater than 20 Percent Aggregate Losses

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- Definition

Line items represent reporting 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
-Sentence Column A

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Amount, before effects of master netting arrangements, of financial assets loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and financial assets transferred other than securities that qualify as secured borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=55761124&loc=SL34722452-111729

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- Definition

Amount of unrealized holding gain (loss) recognized in the income statement for investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Trading Securities
-URI http://asc.fasb.org/extlink&oid=6526789

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(c))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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Investments (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
Investments (Narrative) (Details) - USD ($)	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Investment [Line Items]
Commercial mortgage loans, transferred to affiliates			$ 631,000,000
% of Total	100.00%		100.00%		100.00%
Net change in unrealized gains (losses) from trading account assets supporting insurance liabilities (less than for three months ended 2016)	$ (100,000)	$ 200,000	$ 2,200,000	$ 900,000
Investment Grade Securities Gross Unrealized Losses	26,700,000		26,700,000		$ 133,600,000
Gross unrealized losses related to other than high or highest quality securities	10,200,000		10,200,000		19,200,000
Available For Sale Securities Continuous Unrealized Loss Twelve Months Or Longer	26,600,000		26,600,000		50,400,000
Securities Loaned, Including Not Subject To Master Netting Arrangement And Assets Other Than Securities Transferred	157,000,000		157,000,000		40,000,000
Maturity Overnight
Investment [Line Items]
Securities Loaned, Including Not Subject To Master Netting Arrangement And Assets Other Than Securities Transferred	156,000,000		156,000,000		38,000,000
Maturity Less than 30 Days
Investment [Line Items]
Securities Loaned, Including Not Subject To Master Netting Arrangement And Assets Other Than Securities Transferred	1,000,000		1,000,000		2,000,000
Corporate securities
Investment [Line Items]
Securities Loaned, Including Not Subject To Master Netting Arrangement And Assets Other Than Securities Transferred	152,000,000		152,000,000		33,000,000
Foreign government bonds
Investment [Line Items]
Securities Loaned, Including Not Subject To Master Netting Arrangement And Assets Other Than Securities Transferred	5,000,000		5,000,000		7,000,000
Equity securities
Investment [Line Items]
Gross unrealized losses representing declines in value of greater than 20% (less than in 2015)	$ 0		$ 0		$ 0
California
Investment [Line Items]
% of Total	22.00%		22.00%
Texas
Investment [Line Items]
% of Total	15.00%		15.00%
New Jersey
Investment [Line Items]
% of Total	7.00%		7.00%