Below investment grade assets included in fixed income securities.

No definition available.

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- Definition

This element represents the fixed income securities that do not produce any income.

+ References

No definition available.

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No definition available.

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This element represents the amount of municipal bonds as a percentage of total carrying value.

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- Definition

Interest earned on collateral received for loaned securities and invested in short-term investments and fixed income securities, net of fees.

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Threshold percentage which the entity uses for disclosure.

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No definition available.

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- Definition

Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 320
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75027294&loc=d3e22002-158495

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- Definition

Amount of securities loaned to entities in exchange for collateral, not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226052-175313

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Investments - Securities loaned and Other (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Securities loaned
Fixed income and equity securities loaned	$ 1,090	$ 1,080
Interest Income on collateral, net of fees	7	6	$ 2
Other investment information
Below investment grade assets	7,570	$ 8,620
Fixed income securities and short-term investments deposited with regulatory authorities	154
Non-income producing fixed income securities and other investments	$ 51
Shareholders' equity \| Concentration of credit risk \| Minimum
Municipal Bonds
Percentage of credit concentration risk of single issuer and affiliates of shareholder's equity	10.00%
Texas
Municipal Bonds
Percentage of municipal bonds carrying value	9.60%	10.00%
California
Municipal Bonds
Percentage of municipal bonds carrying value	7.00%	7.20%
New York
Municipal Bonds
Percentage of municipal bonds carrying value	6.90%	6.80%
Florida
Municipal Bonds
Percentage of municipal bonds carrying value	6.50%	5.70%
Washington
Municipal Bonds
Percentage of municipal bonds carrying value	5.40%	5.60%
Michigan
Municipal Bonds
Percentage of municipal bonds carrying value	4.20%	5.40%