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Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions - Commitments (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Company's contractual commitments due to letters of credit
Total letters of credit	$ 11,928	$ 11,527
Fixed
Company's contractual commitments due to letters of credit
Total letters of credit	459	471
Variable
Company's contractual commitments due to letters of credit
Total letters of credit	11,469	11,056
Borrower
Company's contractual commitments due to letters of credit
Total letters of credit	11,353	10,955
Borrower | Fixed
Company's contractual commitments due to letters of credit
Total letters of credit	459	471
Borrower | Variable
Company's contractual commitments due to letters of credit
Total letters of credit	10,894	10,484
Borrower | Financial standby
Company's contractual commitments due to letters of credit
Total letters of credit	3,552	4,800
Borrower | Financial standby | Fixed
Company's contractual commitments due to letters of credit
Total letters of credit	55	55
Borrower | Financial standby | Variable
Company's contractual commitments due to letters of credit
Total letters of credit	3,497	4,745
Borrower | Commercial standby
Company's contractual commitments due to letters of credit
Total letters of credit	47	49
Borrower | Commercial standby | Variable
Company's contractual commitments due to letters of credit
Total letters of credit	47	49
Borrower | Performance standby
Company's contractual commitments due to letters of credit
Total letters of credit	7,754	6,106
Borrower | Performance standby | Fixed
Company's contractual commitments due to letters of credit
Total letters of credit	404	416
Borrower | Performance standby | Variable
Company's contractual commitments due to letters of credit
Total letters of credit	7,350	5,690
Nonborrower
Company's contractual commitments due to letters of credit
Total letters of credit	575	572
Nonborrower | Variable
Company's contractual commitments due to letters of credit
Total letters of credit	575	572
Nonborrower | Performance standby
Company's contractual commitments due to letters of credit
Total letters of credit	575	572
Nonborrower | Performance standby | Variable
Company's contractual commitments due to letters of credit
Total letters of credit	$ 575	$ 572

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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