Bank segment - Credit risk profile - payment activity (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Credit risk profile based on payment activity for loans
30-59 days past due	$ 8,385	$ 8,993
60-89 days past due	2,929	2,711
Greater than 90 days	13,210	13,798
Total past due	24,524	25,502
Current	4,438,895	4,415,487
Total financing receivables	4,463,419	4,440,989	$ 4,295,045
Recorded Investment greater than 90 days and accruing	0	0
Residential 1-4 family
Credit risk profile based on payment activity for loans
30-59 days past due	5,016	6,124
60-89 days past due	1,900	1,732
Greater than 90 days	11,998	12,632
Total past due	18,914	20,488
Current	2,026,443	2,023,717
Total financing receivables	2,045,357	2,044,205	2,019,092
Commercial real estate
Credit risk profile based on payment activity for loans
Current	561,262	531,917
Total financing receivables	561,262	531,917	476,116
Home equity line of credit
Credit risk profile based on payment activity for loans
30-59 days past due	923	1,341
60-89 days past due	284	501
Greater than 90 days	389	194
Total past due	1,596	2,036
Current	818,700	816,779
Total financing receivables	820,296	818,815	790,837
Residential land
Credit risk profile based on payment activity for loans
30-59 days past due	420
60-89 days past due	267
Greater than 90 days	0
Total past due	687
Current	16,586	16,240
Total financing receivables	$ 17,273	16,240	17,189
Recorded Investment greater than 90 days and accruing
Commercial construction
Credit risk profile based on payment activity for loans
Current	$ 62,444	96,438
Total financing receivables	62,444	96,438	80,312
Residential construction
Credit risk profile based on payment activity for loans
Current	19,984	18,961
Total financing receivables	19,984	18,961	17,441
Commercial loans
Credit risk profile based on payment activity for loans
30-59 days past due	907	699
60-89 days past due	147	145
Greater than 90 days	528	569
Total past due	1,582	1,413
Current	820,054	790,344
Total financing receivables	821,636	791,757	782,804
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	1,119	829
60-89 days past due	331	333
Greater than 90 days	295	403
Total past due	1,745	1,565
Current	113,422	121,091
Total financing receivables	$ 115,167	122,656	$ 111,254
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=35738203&loc=SL6953401-111524

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- Definition

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

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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

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5111-111524

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- Definition

Financing receivables that are current.

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- Definition

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

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- Definition

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

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No definition available.

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- 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

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