Bank subsidiary (Details 13) (Class of financing receivables, USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Recorded investment:
With no related allowance recorded	$ 30,120	$ 105,811
With an allowance recorded	34,641	17,878
Recorded investment	64,761	123,689
Unpaid principal balance:
With no related allowance recorded	42,189	124,300
With an allowance recorded	35,919	17,938
Unpaid principal balance	78,108	142,238
Related Allowance	6,799	3,704
Average recorded investment:
With no related allowance recorded	71,308	110,109
With an allowance recorded	21,382	19,816
Average recorded investment	92,690	129,925
Interest income recognized:
With no related allowance recorded	2,703	5,726
With an allowance recorded	848	1,541
Interest income recognized	3,551	7,267
Residential 1-4 family
Recorded investment:
With no related allowance recorded	14,633	19,217
With an allowance recorded	4,803	3,525
Recorded investment	19,436	22,742
Unpaid principal balance:
With no related allowance recorded	20,247	26,614
With an allowance recorded	4,803	3,525
Unpaid principal balance	25,050	30,139
Related Allowance	384	203
Average recorded investment:
With no related allowance recorded	16,688	21,385
With an allowance recorded	4,204	3,527
Average recorded investment	20,892	24,912
Interest income recognized:
With no related allowance recorded	294	282
With an allowance recorded	250	201
Interest income recognized	544	483
Commercial real estate
Recorded investment:
With no related allowance recorded	2,929	13,397
With an allowance recorded	3,821
Recorded investment	6,750	13,397
Unpaid principal balance:
With no related allowance recorded	2,929	13,397
With an allowance recorded	3,840
Unpaid principal balance	6,769	13,397
Related Allowance	535
Average recorded investment:
With no related allowance recorded	7,771	13,404
With an allowance recorded	1,295
Average recorded investment	9,066	13,404
Interest income recognized:
With no related allowance recorded	237	747
Interest income recognized	237	747
Home equity line of credit
Recorded investment:
With no related allowance recorded	581	711
Recorded investment	581	711
Unpaid principal balance:
With no related allowance recorded	1,374	1,612
Unpaid principal balance	1,374	1,612
Average recorded investment:
With no related allowance recorded	632	954
With an allowance recorded	26
Average recorded investment	658	954
Interest income recognized:
With no related allowance recorded	1	6
Interest income recognized	1	6
Residential land
Recorded investment:
With no related allowance recorded	7,691	30,781
With an allowance recorded	9,984	7,792
Recorded investment	17,675	38,573
Unpaid principal balance:
With no related allowance recorded	10,624	39,136
With an allowance recorded	10,364	7,852
Unpaid principal balance	20,988	46,988
Related Allowance	3,221	2,525
Average recorded investment:
With no related allowance recorded	21,589	33,398
With an allowance recorded	7,428	8,158
Average recorded investment	29,017	41,556
Interest income recognized:
With no related allowance recorded	1,185	1,779
With an allowance recorded	575	603
Interest income recognized	1,760	2,382
Commercial loans
Recorded investment:
With no related allowance recorded	4,265	41,680
With an allowance recorded	16,033	6,561
Recorded investment	20,298	48,241
Unpaid principal balance:
With no related allowance recorded	6,994	43,516
With an allowance recorded	16,912	6,561
Unpaid principal balance	23,906	50,077
Related Allowance	2,659	976
Average recorded investment:
With no related allowance recorded	24,605	40,952
With an allowance recorded	8,429	8,131
Average recorded investment	33,034	49,083
Interest income recognized:
With no related allowance recorded	986	2,912
With an allowance recorded	23	737
Interest income recognized	1,009	3,649
Consumer loans
Recorded investment:
With no related allowance recorded	21	25
Recorded investment	21	25
Unpaid principal balance:
With no related allowance recorded	21	25
Unpaid principal balance	21	25
Average recorded investment:
With no related allowance recorded	23	16
Average recorded investment	$ 23	$ 16

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5258-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953550-111524

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