Investments (Unconsolidated Variable Interest Entities) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Variable Interest Entity [Line Items]
Carrying Amount Asset	$ 431,311	$ 449,897
Carrying Amount liability	431,311	449,897
Structured securities
Variable Interest Entity [Line Items]
Carrying Amount Asset	425,294	444,013
Carrying Amount liability	425,294	444,013
Foreign corporate
Variable Interest Entity [Line Items]
Carrying Amount Asset	6,017	5,884
Carrying Amount liability	$ 6,017	$ 5,884

Line items represent financial 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.

No definition available.

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- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph a
-URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5728-111685

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- Definition

Carrying amount of the liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

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