Bank segment (Details 8) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
Credit risk profile based on payment activity for loans
30-59 days past due	$ 8,307	$ 5,781
60-89 days past due	1,486	1,752
Greater than 90 days	16,342	26,227
Total past due	26,135	33,760
Current	4,316,254	4,125,193
Total financing receivables	4,342,389	4,158,953	4,055,389
Recorded Investment greater than 90 days and accruing	525	0
Residential 1-4 family
Credit risk profile based on payment activity for loans
30-59 days past due	6,449	2,728
60-89 days past due	909	622
Greater than 90 days	14,427	15,411
Total past due	21,785	18,761
Current	2,008,552	1,987,246
Total financing receivables	2,030,337	2,006,007	2,015,082
Commercial real estate
Credit risk profile based on payment activity for loans
30-59 days past due	0	0
Greater than 90 days	0	3,770
Total past due	0	3,770
Current	502,356	436,673
Total financing receivables	502,356	440,443	405,037
Home equity line of credit
Credit risk profile based on payment activity for loans
30-59 days past due	578	765
60-89 days past due	166	312
Greater than 90 days	143	960
Total past due	887	2,037
Current	808,104	737,294
Total financing receivables	808,991	739,331	703,210
Residential land
Credit risk profile based on payment activity for loans
30-59 days past due	260	184
60-89 days past due	0	48
Greater than 90 days	525	2,756
Total past due	785	2,988
Current	16,150	13,188
Total financing receivables	16,935	16,176	18,400
Recorded Investment greater than 90 days and accruing	525
Commercial construction
Credit risk profile based on payment activity for loans
Current	87,461	52,112
Total financing receivables	87,461	52,112	51,067
Residential construction
Credit risk profile based on payment activity for loans
Current	18,699	12,774
Total financing receivables	18,699	12,774	10,460
Commercial loans
Credit risk profile based on payment activity for loans
30-59 days past due	239	1,668
60-89 days past due	34	612
Greater than 90 days	954	3,026
Total past due	1,227	5,306
Current	768,852	778,082
Total financing receivables	770,079	783,388	749,733
Recorded Investment greater than 90 days and accruing		0
Consumer loans
Credit risk profile based on payment activity for loans
30-59 days past due	781	436
60-89 days past due	377	158
Greater than 90 days	293	304
Total past due	1,451	898
Current	106,080	107,824
Total financing receivables	107,531	108,722	102,400
Recorded Investment greater than 90 days and accruing		$ 0

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

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=28368275&loc=SL6953401-111524

+ Details

Name:	us-gaap_FinancingReceivableRecordedInvestment30To59DaysPastDue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

+ Details

Name:	us-gaap_FinancingReceivableRecordedInvestment60To89DaysPastDue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5111-111524

+ Details

Name:	us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Financing receivables that are current.

+ References

+ Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

+ Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentEqualToGreaterThan90DaysPastDue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

+ Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentPastDue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Net amount of the 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, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.3)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Article 5

+ Details

Name:	us-gaap_NotesReceivableNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant