Loans, Impaired Loans (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2012	Dec. 31, 2011
Without an allowance recorded [Abstract]
Recorded investment	$ 8,600
With an allowance recorded [Abstract]
Recorded investment	18,900	14,500
Related allowance	7,000	5,900
Total allowance recorded [Abstract]
Total impaired loans	27,500	17,600
Commercial [Member]
Without an allowance recorded [Abstract]
Recorded investment	1,689	900
Unpaid principal balance	3,727	2,042
Related allowance	0	6,831
Average recorded investment	1,284	626
Interest income recognized	0	0
With an allowance recorded [Abstract]
Recorded investment	7,847	5,550
Unpaid principal balance	8,043	5,550
Related allowance	2,739	2,724
Average recorded investment	6,051	3,075
Interest income recognized	0	0
Total allowance recorded [Abstract]
Total impaired loans	9,536	6,450
Unpaid principal balance	11,770	7,592
Related allowance	2,739	9,555
Average recorded investment	7,335	3,701
Interest income recognized	0	0
Commercial mortgage [Member]
Without an allowance recorded [Abstract]
Recorded investment	3,482	0
Unpaid principal balance	4,027	0
Related allowance	0	0
Average recorded investment	1,550	310
Interest income recognized	0	0
With an allowance recorded [Abstract]
Recorded investment	4,508	3,672
Unpaid principal balance	5,052	3,672
Related allowance	902	712
Average recorded investment	5,089	2,793
Interest income recognized	0	0
Total allowance recorded [Abstract]
Total impaired loans	7,990	3,672
Unpaid principal balance	9,079	3,672
Related allowance	903	712
Average recorded investment	6,639	3,103
Interest income recognized	0	0
Construction [Member]
Without an allowance recorded [Abstract]
Recorded investment	2,541	0
Unpaid principal balance	5,781	0
Related allowance	0	0
Average recorded investment	1,123	100
Interest income recognized	0	0
With an allowance recorded [Abstract]
Recorded investment	6,433	4,949
Unpaid principal balance	7,249	4,949
Related allowance	3,303	2,296
Average recorded investment	7,069	2,123
Interest income recognized	0	0
Total allowance recorded [Abstract]
Total impaired loans	8,974	4,949
Unpaid principal balance	13,030	4,949
Related allowance	3,303	2,296
Average recorded investment	8,192	2,223
Interest income recognized	0	0
Residential mortgage [Member]
Without an allowance recorded [Abstract]
Recorded investment	0	1,264
Unpaid principal balance	0	1,414
Related allowance	0	149
Average recorded investment	421	662
Interest income recognized	0	0
With an allowance recorded [Abstract]
Recorded investment	95	0
Unpaid principal balance	95	0
Related allowance	73	0
Average recorded investment	31	5,048
Interest income recognized	0	0
Total allowance recorded [Abstract]
Total impaired loans	95	1,264
Unpaid principal balance	95	1,414
Related allowance	73	149
Average recorded investment	452	5,710
Interest income recognized	0	0
Consumer - home equity [Member]
Without an allowance recorded [Abstract]
Recorded investment	927	927
Unpaid principal balance	927	927
Related allowance	0	3,765
Average recorded investment	927	371
Interest income recognized	0	0
With an allowance recorded [Abstract]
Recorded investment	0	325
Unpaid principal balance	0	325
Related allowance	0	204
Average recorded investment	108	510
Interest income recognized	0	0
Total allowance recorded [Abstract]
Total impaired loans	927	1,252
Unpaid principal balance	927	1,252
Related allowance	0	3,969
Average recorded investment	1,035	881
Interest income recognized	$ 0	$ 0