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.

+ References

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=64858031&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=63488584&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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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563

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Investments (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
Investments (Narrative) (Details) - USD ($)	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Investment [Line Items]
Investment Grade Securities Gross Unrealized Losses	$ 22,600,000		$ 22,600,000		$ 133,600,000
Gross unrealized losses related to other than high or highest quality securities	7,900,000		7,900,000		19,200,000
Available For Sale Securities Continuous Unrealized Loss Twelve Months Or Longer	19,800,000		19,800,000		$ 50,400,000
Net change in unrealized gains (losses) from trading account assets supporting insurance liabilities (less than for three months ended 2016)	$ 1,400,000	$ (2,800,000)	$ 3,500,000	$ (2,200,000)
% of Total	100.00%		100.00%		100.00%
Commercial mortgage loans, transferred to affiliates			$ 631,000,000
Securities Loaned, Including Not Subject To Master Netting Arrangement And Assets Other Than Securities Transferred	$ 134,000,000		134,000,000		$ 40,000,000
Maturity Overnight
Investment [Line Items]
Securities Loaned, Including Not Subject To Master Netting Arrangement And Assets Other Than Securities Transferred	134,000,000		134,000,000		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					2,000,000
Corporate securities
Investment [Line Items]
Securities Loaned, Including Not Subject To Master Netting Arrangement And Assets Other Than Securities Transferred	85,000,000		85,000,000		33,000,000
US Treasury securities
Investment [Line Items]
Securities Loaned, Including Not Subject To Master Netting Arrangement And Assets Other Than Securities Transferred	$ 49,000,000		$ 49,000,000
Foreign government bonds
Investment [Line Items]
Securities Loaned, Including Not Subject To Master Netting Arrangement And Assets Other Than Securities Transferred					7,000,000
California
Investment [Line Items]
% of Total	21.00%		21.00%
Texas
Investment [Line Items]
% of Total	16.00%		16.00%
Illinois
Investment [Line Items]
% of Total	7.00%		7.00%
Equity securities
Investment [Line Items]
Gross unrealized losses representing declines in value of greater than 20% (less than in 2015)	$ 0		$ 0		$ 0