(Summary of nonperforming loans) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Summary of nonperforming loans
Total nonperforming TDRs	$ 101,322	$ 94,943
Total loans	5,688,230	4,647,621
Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	50,644	61,897
Total accruing loans contractually past due 90 days or more as to interest or principal payments	2,073	1,997
Commercial Loan Portfolio [Member]
Summary of nonperforming loans
Total nonperforming TDRs	77,047	72,214
Total loans	3,084,024	2,518,826
Consumer Loan Portfolio [Member]
Summary of nonperforming loans
Total nonperforming TDRs	24,275	22,729
Total loans	2,604,206	2,128,795
Commercial [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	16,418	18,374
Total accruing loans contractually past due 90 days or more as to interest or principal payments	170	536
Real estate commercial [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	24,966	28,598
Total accruing loans contractually past due 90 days or more as to interest or principal payments	0	190
Real Estate Construction Loans [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	162	371
Total accruing loans contractually past due 90 days or more as to interest or principal payments	0	0
Land Development Loans [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	225	2,309
Total accruing loans contractually past due 90 days or more as to interest or principal payments	0	0
Real estate residential [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	6,706	8,921
Total accruing loans contractually past due 90 days or more as to interest or principal payments	557	537
Consumer Installment Loans [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	500	676
Total accruing loans contractually past due 90 days or more as to interest or principal payments	0	0
Home Equity Loans [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	1,667	2,648
Total accruing loans contractually past due 90 days or more as to interest or principal payments	1,346	734
Nonperforming [Member]
Summary of nonperforming loans
Total nonaccrual loans	50,644	61,897
Total accruing loans contractually past due 90 days or more as to interest or principal payments	2,073	1,997
Total nonperforming TDRs	18,467	18,090
Total loans	71,184	81,984
Nonperforming [Member] \| Commercial Loan Portfolio [Member]
Summary of nonperforming loans
Total nonperforming TDRs	15,271	13,414
Nonperforming [Member] \| Consumer Loan Portfolio [Member]
Summary of nonperforming loans
Total nonperforming TDRs	3,196	4,676
Nonperforming [Member] \| Commercial [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	16,418	18,374
Total accruing loans contractually past due 90 days or more as to interest or principal payments	170	536
Nonperforming [Member] \| Real estate commercial [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	24,966	28,598
Total accruing loans contractually past due 90 days or more as to interest or principal payments	0	190
Nonperforming [Member] \| Real Estate Construction Loans [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	162	371
Nonperforming [Member] \| Land Development Loans [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	225	2,309
Nonperforming [Member] \| Real estate residential [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	6,706	8,921
Total accruing loans contractually past due 90 days or more as to interest or principal payments	557	537
Nonperforming [Member] \| Consumer Installment Loans [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	500	676
Nonperforming [Member] \| Home Equity Loans [Member] \| Originated Portfolio Segment [Member]
Summary of nonperforming loans
Total nonaccrual loans	1,667	2,648
Total accruing loans contractually past due 90 days or more as to interest or principal payments	$ 1,346	$ 734

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

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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

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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