Loans and reserve for credit losses (Details 3) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Commercial real estate:
Owner occupied	$ 207,060	$ 196,821
Non-owner occupied	326,817	328,480
Total commercial real estate loans	533,877	525,301
Construction	48,205	45,650
Residential real estate	95,775	85,494
Commercial and industrial	196,977	162,213
Consumer	37,740	39,506
Recorded investment in loans Total	912,574	858,164
Acceptable [Member]
Commercial real estate:
Owner occupied	129,906	122,125
Non-owner occupied	227,647	214,990
Total commercial real estate loans	357,553	337,115
Construction	38,047	25,308
Residential real estate	89,592	74,576
Commercial and industrial	179,681	126,208
Consumer	37,134	37,264
Recorded investment in loans Total	702,007	600,471
Pass-Watch [Member]
Commercial real estate:
Owner occupied	25,246	26,326
Non-owner occupied	64,932	39,879
Total commercial real estate loans	90,178	66,205
Construction	5,675	6,079
Residential real estate	1,794	2,207
Commercial and industrial	5,180	7,005
Consumer	605	603
Recorded investment in loans Total	103,432	82,099
Special Mention [Member]
Commercial real estate:
Owner occupied	23,366	13,622
Non-owner occupied	18,706	24,910
Total commercial real estate loans	42,072	38,532
Construction	1,055	1,795
Residential real estate	1,294	2,086
Commercial and industrial	4,502	6,473
Consumer	0	0
Recorded investment in loans Total	48,923	48,886
Substandard [Member]
Commercial real estate:
Owner occupied	28,542	34,748
Non-owner occupied	15,532	48,701
Total commercial real estate loans	44,074	83,449
Construction	3,428	12,468
Residential real estate	3,095	6,625
Commercial and industrial	7,614	22,527
Consumer	1	1,639
Recorded investment in loans Total	$ 58,212	$ 126,708

Amount before allowance of consumer loans, including, but not limited to, mortgage, home equity, vehicles, credit card, installment, and lease financing. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References+ Details

Amount before allowance of consumer real estate loans. Includes, but not limited to, construction financing, residential mortgage loans, and home equity lines of credit. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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- Definition

Amount before allowance of commercial loans to acquire real property. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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- Definition

Amount before allowance of loans issued to commercial and industrial institutions. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes real estate loans and loans covered under loss sharing agreements.

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- Definition

Amount before allowance of commercial construction loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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- Definition

Amount before allowance of commercial loans issued to businesses to acquire, develop, construct, improve, or refinance land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5066-111524

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph e

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 60

-Paragraph 47

-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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

Reference 5: 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(a))

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(c))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 51, 52, 53

-IssueDate 2006-05-01

-Chapter 8

-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.

+ Details