Allowance for Loan Losses Financing Receivable and Allowance Element by Class (Details) (USD $)	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	$ 12,670,000	$ 12,720,000	$ 12,500,000	$ 14,384,000	$ 12,954,000	$ 13,000,000
Specific Reserves Evaluated Individually for Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	3,006,000		3,539,000	4,177,000
General Reserves Based on Historical Loss Experience [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	4,287,000		4,304,000	4,648,000
Reserve for Qualitative Factors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	4,102,000		3,815,000	3,664,000
Unallocated Reserves [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	1,275,000		842,000	1,895,000
Commercial Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	5,811,000	5,879,000	5,865,000	5,564,000	5,862,000	5,659,000
Commercial Real Estate Portfolio Segment [Member] \| Specific Reserves Evaluated Individually for Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	1,510,000		1,523,000	1,133,000
Commercial Real Estate Portfolio Segment [Member] \| General Reserves Based on Historical Loss Experience [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	2,148,000		2,369,000	2,685,000
Commercial Real Estate Portfolio Segment [Member] \| Reserve for Qualitative Factors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	2,153,000		1,973,000	1,746,000
Commercial Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	591,000	1,064,000	1,359,000	1,373,000	704,000	658,000
Commercial Construction [Member] \| Specific Reserves Evaluated Individually for Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	266,000		969,000	787,000
Commercial Construction [Member] \| General Reserves Based on Historical Loss Experience [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	162,000		213,000	355,000
Commercial Construction [Member] \| Reserve for Qualitative Factors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	163,000		177,000	231,000
Commercial Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	2,572,000	2,115,000	2,050,000	2,476,000	2,125,000	2,063,000
Commercial Other [Member] \| Specific Reserves Evaluated Individually for Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	1,005,000		652,000	932,000
Commercial Other [Member] \| General Reserves Based on Historical Loss Experience [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	783,000		763,000	935,000
Commercial Other [Member] \| Reserve for Qualitative Factors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	784,000		635,000	609,000
Municipal [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	18,000	18,000	18,000	19,000	19,000	19,000
Municipal [Member] \| Specific Reserves Evaluated Individually for Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses			0	0
Municipal [Member] \| General Reserves Based on Historical Loss Experience [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses			0	0
Municipal [Member] \| Reserve for Qualitative Factors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	18,000		18,000	19,000
Residential Term [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	1,026,000	1,113,000	1,109,000	1,587,000	1,236,000	1,159,000
Residential Term [Member] \| Specific Reserves Evaluated Individually for Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	218,000		395,000	966,000
Residential Term [Member] \| General Reserves Based on Historical Loss Experience [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	380,000		278,000	165,000
Residential Term [Member] \| Reserve for Qualitative Factors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	428,000		436,000	456,000
Residential Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	9,000	9,000	11,000	58,000	59,000	255,000
Residential Construction [Member] \| Specific Reserves Evaluated Individually for Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	0		0	48,000
Residential Construction [Member] \| General Reserves Based on Historical Loss Experience [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	4,000		4,000	2,000
Residential Construction [Member] \| Reserve for Qualitative Factors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	5,000		7,000	8,000
Home Equity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	737,000	859,000	654,000	809,000	682,000	595,000
Home Equity [Member] \| Specific Reserves Evaluated Individually for Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	7,000		0	300,000
Home Equity [Member] \| General Reserves Based on Historical Loss Experience [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	402,000		315,000	155,000
Home Equity [Member] \| Reserve for Qualitative Factors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	328,000		339,000	354,000
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	631,000	574,000	592,000	603,000	568,000	584,000
Consumer Portfolio Segment [Member] \| Specific Reserves Evaluated Individually for Impairment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	0		0	11,000
Consumer Portfolio Segment [Member] \| General Reserves Based on Historical Loss Experience [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	408,000		362,000	351,000
Consumer Portfolio Segment [Member] \| Reserve for Qualitative Factors [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	223,000		230,000	241,000
Unallocated Financing Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	1,275,000	1,089,000	842,000	1,895,000	1,699,000	2,008,000
Unallocated Financing Receivables [Member] \| Unallocated Reserves [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	$ 1,275,000		$ 842,000	$ 1,895,000

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

-Paragraph 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 8, 9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Section 563c.102

-Paragraph 8

-Subparagraph a(ii)

-Chapter V

-Subsection I

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

+ Details