Investments (Trading Account Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Major Types of Investment Securities [Line Items]
Amortized Cost	$ 35,484	$ 65,326
Fair Value	35,328	64,612
Fixed maturities, available-for-sale
Major Types of Investment Securities [Line Items]
Amortized Cost	23,555	50,565
Fair Value	19,558	46,364
Equity securities, available-for-sale:
Major Types of Investment Securities [Line Items]
Amortized Cost	11,929	14,761
Fair Value	$ 15,770	$ 18,248

Major Types of Investment Securities [Line Items]

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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Amount of investments in debt securities classified as trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6526789

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Fair value of investments in trading equity securities and other forms of trading securities that provide ownership interests.

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