Allowance for Loan Losses - Bank's Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	$ 10,800		$ 10,150	$ 9,915	$ 9,915
Provision for loan losses	570	$ 0	1,473	235	235
Charge-offs	(70)		(323)
Ending Balance	11,300		11,300		10,150
Residential Properties
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	6,628		6,586	6,157	6,157
Provision for loan losses	291		333		429
Ending Balance	6,919		6,919		6,586
Commercial Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	1,912		1,526	1,440	1,440
Provision for loan losses	298		924		86
Charge-offs	(70)		(310)
Ending Balance	2,140		2,140		1,526
Commercial and Industrial Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	1,917		1,897	2,149	2,149
Provision for loan losses	77		110		(252)
Charge-offs			(13)
Ending Balance	1,994		1,994		1,897
Consumer Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	343		141	$ 169	169
Provision for loan losses	(96)		106		(28)
Ending Balance	$ 247		$ 247		$ 141

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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-Publisher SEC

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-Number Topic 6

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Amount of expense related to estimated loss from loan and lease transactions.

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