Allowance for Loan Losses - Bank's Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	$ 18,400	$ 15,400
Provision for loan losses	1,688	69
Charge-offs	(88)
Recoveries		231
Ending Balance	20,000	15,700
Residential Properties
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	9,715	6,669
Provision for loan losses	193	1,748
Ending Balance	9,908	8,417
Commercial Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	4,399	2,983
Provision for loan losses	(9)	339
Ending Balance	4,390	3,322
Commercial and Industrial Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	3,624	5,227
Provision for loan losses	1,557	(2,057)
Charge-offs	(88)
Recoveries		231
Ending Balance	5,093	3,401
Consumer Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	267	288
Provision for loan losses	7	9
Ending Balance	274	297
Land
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	395	233
Provision for loan losses	(60)	30
Ending Balance	$ 335	$ 263

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 recovery of financing receivables doubtful of collection that were previously charged off.

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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 FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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Amount of expense related to estimated loss from loan and lease transactions.

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-Name Accounting Standards Codification
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