Bank subsidiary (Details 8) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Credit risk profile based on payment activity for loans
30-59 days past due	$ 15,386	$ 15,193
60-89 days past due	11,918	6,729
Greater than 90 days	50,536	44,397
Total past due	77,840	66,319
Current	3,646,215	3,628,216
Total financing receivables	3,724,055	3,694,535
Recorded Investment greater than 90 days and accruing	362	541
Residential 1-4 family
Credit risk profile based on payment activity for loans
30-59 days past due	8,111	10,391
60-89 days past due	6,236	4,583
Greater than 90 days	29,575	28,113
Total past due	43,922	43,087
Current	1,851,520	1,883,687
Total financing receivables	1,895,442	1,926,774
Commercial real estate
Credit risk profile based on payment activity for loans
30-59 days past due	3,955
Greater than 90 days	3,436
Total past due	7,391
Current	344,325	331,931
Total financing receivables	351,716	331,931
Home equity line of credit
Credit risk profile based on payment activity for loans
30-59 days past due	1,007	1,671
60-89 days past due	545	494
Greater than 90 days	1,816	1,421
Total past due	3,368	3,586
Current	559,018	531,895
Total financing receivables	562,386	535,481
Residential land
Credit risk profile based on payment activity for loans
30-59 days past due	261	2,352
60-89 days past due	24	575
Greater than 90 days	10,777	13,037
Total past due	11,062	15,964
Current	27,963	29,428
Total financing receivables	39,025	45,392
Recorded Investment greater than 90 days and accruing		205
Commercial construction
Credit risk profile based on payment activity for loans
Current	47,850	41,950
Total financing receivables	47,850	41,950
Residential construction
Credit risk profile based on payment activity for loans
Current	3,082	3,327
Total financing receivables	3,082	3,327
Commercial loans
Credit risk profile based on payment activity for loans
30-59 days past due	1,410	226
60-89 days past due	4,815	733
Greater than 90 days	4,476	1,340
Total past due	10,701	2,299
Current	716,591	714,128
Total financing receivables	727,292	716,427
Recorded Investment greater than 90 days and accruing	52	28
Consumer loans
Credit risk profile based on payment activity for loans
30-59 days past due	642	553
60-89 days past due	298	344
Greater than 90 days	456	486
Total past due	1,396	1,383
Current	95,866	91,870
Total financing receivables	97,262	93,253
Recorded Investment greater than 90 days and accruing	$ 310	$ 308

The amount of the recorded investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, accounts receivable (with terms exceeding one year), notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Receivable

-URI http://asc.fasb.org/extlink&oid=6953735

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Financing receivables that are less than 60 days past due but more than 29 days past due.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953401-111524

+ Details

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Period Type:	instant

- Definition

Financing receivables that are less than 90 days past due but more than 59 days past due.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5111-111524

-Subparagraph (d)

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- Definition

Financing receivables that are current.

+ References

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Data Type:	xbrli:monetaryItemType
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- Definition

Financing receivables that are equal to or greater than 90 days past due.

+ References

+ Details

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

+ Details

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