Investments and Derivative Instruments Level 4 Fair Value Hedges (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2015
Fair Value Hedges [Line Items]
Ineffectiveness on Interest Rate Fair Value Hedges is Immaterial	1	1	1

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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