Loans, net and allowance for loan losses, Changes in the Allowance for Loan Losses Account by Major Classification of Loans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Changes in the allowance for loan losses account by major classification of loan [Roll Forward]
Beginning Balance	$ 6,735	$ 5,916	$ 6,581	$ 5,349
Charge-offs	(70)	(102)	(344)	(607)
Recoveries	5	153	103	190
Provisions	165	330	495	1,365
Ending balance	6,835	6,297	6,835	6,297
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance	6,835	6,297	6,835	6,297
Ending balance: individually evaluated for impairment	1,107		1,107		855
Ending balance: collectively evaluated for impairment	5,728		5,728		5,726
Loans receivable [Abstract]
Ending balance	505,109		505,109		465,773
Ending balance: individually evaluated for impairment	18,554		18,554		13,834
Ending balance: collectively evaluated for impairment	486,555		486,555		451,939
Commercial [Member]
Changes in the allowance for loan losses account by major classification of loan [Roll Forward]
Beginning Balance	2,711	2,117	2,024	2,047
Charge-offs	(46)	(12)	(46)	(219)
Recoveries	(2)	1	2	2
Provisions	18	(10)	701	266
Ending balance	2,681	2,096	2,681	2,096
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance	2,681	2,096	2,681	2,096
Ending balance: individually evaluated for impairment	386		386		327
Ending balance: collectively evaluated for impairment	2,295		2,295		1,697
Loans receivable [Abstract]
Ending balance	187,462		187,462		170,379
Ending balance: individually evaluated for impairment	3,275		3,275		5,169
Ending balance: collectively evaluated for impairment	184,187		184,187		165,210
Real Estate Commercial [Member]
Changes in the allowance for loan losses account by major classification of loan [Roll Forward]
Beginning Balance	2,831	1,970	2,101	1,515
Charge-offs			(58)	(100)
Provisions	(1)	21	787	576
Ending balance	2,830	1,991	2,830	1,991
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance	2,830	1,991	2,830	1,991
Ending balance: individually evaluated for impairment	424		424		239
Ending balance: collectively evaluated for impairment	2,406		2,406		1,862
Loans receivable [Abstract]
Ending balance	181,557		181,557		158,798
Ending balance: individually evaluated for impairment	13,388		13,388		7,137
Ending balance: collectively evaluated for impairment	168,169		168,169		151,661
Real Estate Residential [Member]
Changes in the allowance for loan losses account by major classification of loan [Roll Forward]
Beginning Balance	886	819	1,206	761
Charge-offs			(187)	(21)
Recoveries	(2)		77
Provisions	65	137	(147)	216
Ending balance	949	956	949	956
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance	949	956	949	956
Ending balance: individually evaluated for impairment	297		297		283
Ending balance: collectively evaluated for impairment	652		652		923
Loans receivable [Abstract]
Ending balance	117,796		117,796		117,527
Ending balance: individually evaluated for impairment	1,891		1,891		1,522
Ending balance: collectively evaluated for impairment	115,905		115,905		116,005
Consumer [Member]
Changes in the allowance for loan losses account by major classification of loan [Roll Forward]
Beginning Balance	176	197	234	198
Charge-offs	(24)	(90)	(53)	(267)
Recoveries	9	152	24	188
Provisions	16	(68)	(28)	72
Ending balance	177	191	177	191
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance	177	191	177	191
Ending balance: individually evaluated for impairment					6
Ending balance: collectively evaluated for impairment	177		177		228
Loans receivable [Abstract]
Ending balance	18,294		18,294		19,069
Ending balance: individually evaluated for impairment					6
Ending balance: collectively evaluated for impairment	18,294		18,294		19,063
Unallocated [Member]
Changes in the allowance for loan losses account by major classification of loan [Roll Forward]
Beginning Balance	131	813	1,016	828
Provisions	67	250	(818)	235
Ending balance	198	1,063	198	1,063
Allowance for Loan and Lease Losses [Roll Forward]
Ending balance	198	1,063	198	1,063
Ending balance: collectively evaluated for impairment	$ 198		$ 198		$ 1,016

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A valuation allowance for financing receivables that are expected to be uncollectible.

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

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Amount of direct write-downs of financing receivables charged against the allowance.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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