Commitments and Contingencies Other Narratives (Details) $ in Thousands	Dec. 31, 2015 USD ($) Number_of_states	Dec. 31, 2014 USD ($)
Loss Contingencies [Line Items]
Present value of credit enhancement fees	$ 343
FHLB MPF Program Remaining Outstanding Balance of Loans Sold	139,152	$ 164,750
Standby letters of credit [Member]
Loss Contingencies [Line Items]
Guarantor obligations, current carrying value	$ 0	$ 0
States other than Iowa [Member] \| State and political subdivisions [Member]
Loss Contingencies [Line Items]
Investment securities, number of states, debt securities \| Number_of_states	17
State of Iowa [Member] \| State and political subdivisions [Member]
Loss Contingencies [Line Items]
Investment securities, single state concentration, percent of balance of state and political subdivision securities	45.00%

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

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- Definition

Commitments and Contingencies Disclosure [Line Items]

+ References

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- Definition

FHLB MPF Program Remaining Outstanding Balance of Loans Sold

+ References

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- Definition

Investment securities issued by single state, percent of balance of state and political subdivision securities.

+ References

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- Definition

Debt securities concentration by states, number of states.

+ References

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- Definition

The liability represented by the present value of the credit enhancement fees less any expected losses in the mortgages delivered under the Mortgage Partnership Finance program with the FHLB of Des Moines.

+ References

No definition available.

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