Derivatives (Earned Income On Derivatives - Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Derivatives Designated as Hedging Instruments: \| Net investment income
Derivative Instruments, Gain (Loss) [Line Items]
Total earned income	$ 124	$ 148
Derivatives Not Designated or Not Qualifying as Hedging Instruments: \| Net derivative gains (losses)
Derivative Instruments, Gain (Loss) [Line Items]
Total earned income	$ 84	$ 63

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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