Investments - Commercial Mortgage Loan Maturities (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Investments:
Commercial Mortgage Loans	$ 1,684	$ 1,666

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(c))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Balance Type:	debit
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