Loans and Allowance for Loan Losses - Aging of the recorded investment in past due loans (Details 5) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012
Aging of the recorded investment in past due loans
Total loans	$ 4,193,560	$ 4,175,008	$ 4,127,566
Loans Receivable
Aging of the recorded investment in past due loans
Loans Past Due, 30 - 59 Days	24,634	27,732	31,926
Loans Past Due, 60 - 89 Days	7,913	8,266	10,573
Loans Past Due, Greater than 90 Days Past Due	18,140	23,129	46,636
Loans, Total Past Due	50,687	59,127	89,135
Loans Not Past Due	4,142,873	4,115,881	4,038,431
Total loans	4,193,560	4,175,008	4,127,566
Loans Receivable \| Commercial (secured by real estate)
Aging of the recorded investment in past due loans
Total loans	1,804,030	1,813,365	1,843,207
Loans Receivable \| Commercial & industrial
Aging of the recorded investment in past due loans
Total loans	453,764	458,246	439,496
Loans Receivable \| Commercial construction
Aging of the recorded investment in past due loans
Total loans	152,410	154,769	167,122
Loans Receivable \| Residential mortgage
Aging of the recorded investment in past due loans
Loans Past Due, 30 - 59 Days	11,899	12,292	14,540
Loans Past Due, 60 - 89 Days	2,667	2,426	5,223
Loans Past Due, Greater than 90 Days Past Due	4,159	4,848	9,103
Loans, Total Past Due	18,725	19,566	28,866
Loans Not Past Due	1,227,250	1,194,637	1,102,382
Total loans	1,245,975	1,214,203	1,131,248
Loans Receivable \| Residential construction
Aging of the recorded investment in past due loans
Loans Past Due, 30 - 59 Days	2,310	2,233	7,462
Loans Past Due, 60 - 89 Days	2,371	1,934	1,584
Loans Past Due, Greater than 90 Days Past Due	2,373	5,159	11,201
Loans, Total Past Due	7,054	9,326	20,247
Loans Not Past Due	364,679	372,351	415,128
Total loans	371,733	381,677	435,375
Loans Receivable \| Consumer installment
Aging of the recorded investment in past due loans
Loans Past Due, 30 - 59 Days	682	1,320	961
Loans Past Due, 60 - 89 Days	152	245	248
Loans Past Due, Greater than 90 Days Past Due	109	289	346
Loans, Total Past Due	943	1,854	1,555
Loans Not Past Due	164,705	150,894	109,563
Total loans	165,648	152,748	111,118
Loans Receivable \| Commercial Portfolio Segment
Aging of the recorded investment in past due loans
Loans Past Due, 30 - 59 Days	9,743	11,887	8,963
Loans Past Due, 60 - 89 Days	2,723	3,661	3,518
Loans Past Due, Greater than 90 Days Past Due	11,499	12,833	25,986
Loans, Total Past Due	23,965	28,381	38,467
Loans Not Past Due	2,386,239	2,397,999	2,411,358
Total loans	2,410,204	2,426,380	2,449,825
Loans Receivable \| Commercial Portfolio Segment \| Commercial (secured by real estate)
Aging of the recorded investment in past due loans
Loans Past Due, 30 - 59 Days	7,402	8,106	6,777
Loans Past Due, 60 - 89 Days	2,304	3,232	3,219
Loans Past Due, Greater than 90 Days Past Due	5,750	7,476	14,461
Loans, Total Past Due	15,456	18,814	24,457
Loans Not Past Due	1,788,574	1,794,551	1,818,750
Total loans	1,804,030	1,813,365	1,843,207
Loans Receivable \| Commercial Portfolio Segment \| Commercial & industrial
Aging of the recorded investment in past due loans
Loans Past Due, 30 - 59 Days	1,485	1,565	1,930
Loans Past Due, 60 - 89 Days	419	429	244
Loans Past Due, Greater than 90 Days Past Due	219	867	2,905
Loans, Total Past Due	2,123	2,861	5,079
Loans Not Past Due	451,641	455,385	434,417
Total loans	453,764	458,246	439,496
Loans Receivable \| Commercial Portfolio Segment \| Commercial construction
Aging of the recorded investment in past due loans
Loans Past Due, 30 - 59 Days	856	2,216	256
Loans Past Due, 60 - 89 Days			55
Loans Past Due, Greater than 90 Days Past Due	5,530	4,490	8,620
Loans, Total Past Due	6,386	6,706	8,931
Loans Not Past Due	146,024	148,063	158,191
Total loans	$ 152,410	$ 154,769	$ 167,122

Financing receivable recorded investment loans not past due.

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

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

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

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

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- Definition

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

+ References

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