Loans and Leases (Impaired loans not covered by loss share agreements) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Dec. 31, 2014
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Impaired loans with a related allowance, Unpaid Contractual Balance	$ 12,453	$ 12,453	$ 16,664
Impaired loans without a related allowance, Unpaid Contractual Balance	68,487	68,487	53,132
Total impaired loans held to maturity, Unpaid Contractual Balance	80,940	80,940	69,796
Impaired Financing Receivable, Recorded Investment [Abstract]
Impaired loans with a related allowance, Loan Balance	12,024	12,024	16,462
Impaired loans without a related allowance, Loan Balance	64,909	64,909	45,262
Total impaired loans held to maturity, Loan Balance	76,933	76,933	61,724
Impaired loans, Related Allowance Recorded	2,502	2,502	2,697
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Impaired loans with a related allowance, Avg. Loan Balance	10,914	10,933	22,942
Impaired loans without a related allowance, Avg. Loan Balance	66,762	56,672	39,466
Total impaired loans held to maturity, Avg. Loan Balance	77,676	67,605	62,408
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract]
Impaired loans with a related allowance, Interest Income Recognized	110	184	457
Impaired loans without a related allowance, Interest Income Recognized	516	1,450	1,523
Total impaired loans held to maturity, Interest Income Recognized	626	1,634	1,980
Commercial
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Impaired loans with a related allowance, Unpaid Contractual Balance	1,200	1,200	780
Impaired loans without a related allowance, Unpaid Contractual Balance	7,518	7,518	4,913
Total impaired loans held to maturity, Unpaid Contractual Balance	8,718	8,718	5,693
Impaired Financing Receivable, Recorded Investment [Abstract]
Impaired loans with a related allowance, Loan Balance	948	948	780
Impaired loans without a related allowance, Loan Balance	7,438	7,438	3,746
Total impaired loans held to maturity, Loan Balance	8,386	8,386	4,526
Impaired loans, Related Allowance Recorded	388	388	754
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Impaired loans with a related allowance, Avg. Loan Balance	394	383	5,594
Impaired loans without a related allowance, Avg. Loan Balance	9,759	7,050	3,499
Total impaired loans held to maturity, Avg. Loan Balance	10,153	7,433	9,093
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract]
Impaired loans with a related allowance, Interest Income Recognized	3	9	19
Impaired loans without a related allowance, Interest Income Recognized	100	274	101
Total impaired loans held to maturity, Interest Income Recognized	103	283	120
Commercial real estate
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Impaired loans with a related allowance, Unpaid Contractual Balance	2,384	2,384	7,356
Impaired loans without a related allowance, Unpaid Contractual Balance	44,758	44,758	32,708
Total impaired loans held to maturity, Unpaid Contractual Balance	47,142	47,142	40,064
Impaired Financing Receivable, Recorded Investment [Abstract]
Impaired loans with a related allowance, Loan Balance	2,384	2,384	7,322
Impaired loans without a related allowance, Loan Balance	41,298	41,298	28,449
Total impaired loans held to maturity, Loan Balance	43,682	43,682	35,771
Impaired loans, Related Allowance Recorded	645	645	636
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Impaired loans with a related allowance, Avg. Loan Balance	1,243	2,028	5,931
Impaired loans without a related allowance, Avg. Loan Balance	42,476	36,149	24,522
Total impaired loans held to maturity, Avg. Loan Balance	43,719	38,177	30,453
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract]
Impaired loans with a related allowance, Interest Income Recognized	10	20	303
Impaired loans without a related allowance, Interest Income Recognized	397	1,055	1,172
Total impaired loans held to maturity, Interest Income Recognized	407	1,075	1,475
Commercial and commercial real estate
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Impaired loans with a related allowance, Unpaid Contractual Balance	3,584	3,584	8,136
Impaired loans without a related allowance, Unpaid Contractual Balance	52,276	52,276	37,621
Total impaired loans held to maturity, Unpaid Contractual Balance	55,860	55,860	45,757
Impaired Financing Receivable, Recorded Investment [Abstract]
Impaired loans with a related allowance, Loan Balance	3,332	3,332	8,102
Impaired loans without a related allowance, Loan Balance	48,736	48,736	32,195
Total impaired loans held to maturity, Loan Balance	52,068	52,068	40,297
Impaired loans, Related Allowance Recorded	1,033	1,033	1,390
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Impaired loans with a related allowance, Avg. Loan Balance	1,637	2,411	11,525
Impaired loans without a related allowance, Avg. Loan Balance	52,235	43,199	28,021
Total impaired loans held to maturity, Avg. Loan Balance	53,872	45,610	39,546
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract]
Impaired loans with a related allowance, Interest Income Recognized	13	29	322
Impaired loans without a related allowance, Interest Income Recognized	497	1,329	1,273
Total impaired loans held to maturity, Interest Income Recognized	510	1,358	1,595
Agricultural and agricultural real estate
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Impaired loans with a related allowance, Unpaid Contractual Balance	3,196	3,196	3,317
Impaired loans without a related allowance, Unpaid Contractual Balance	2,720	2,720	3,961
Total impaired loans held to maturity, Unpaid Contractual Balance	5,916	5,916	7,278
Impaired Financing Receivable, Recorded Investment [Abstract]
Impaired loans with a related allowance, Loan Balance	3,196	3,196	3,317
Impaired loans without a related allowance, Loan Balance	2,720	2,720	1,732
Total impaired loans held to maturity, Loan Balance	5,916	5,916	5,049
Impaired loans, Related Allowance Recorded	40	40	52
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Impaired loans with a related allowance, Avg. Loan Balance	3,281	3,058	3,966
Impaired loans without a related allowance, Avg. Loan Balance	2,197	2,106	3,308
Total impaired loans held to maturity, Avg. Loan Balance	5,478	5,164	7,274
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract]
Impaired loans with a related allowance, Interest Income Recognized	85	123	104
Impaired loans without a related allowance, Interest Income Recognized	0	9	13
Total impaired loans held to maturity, Interest Income Recognized	85	132	117
Residential real estate
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Impaired loans with a related allowance, Unpaid Contractual Balance	2,637	2,637	2,412
Impaired loans without a related allowance, Unpaid Contractual Balance	11,593	11,593	8,200
Total impaired loans held to maturity, Unpaid Contractual Balance	14,230	14,230	10,612
Impaired Financing Receivable, Recorded Investment [Abstract]
Impaired loans with a related allowance, Loan Balance	2,469	2,469	2,244
Impaired loans without a related allowance, Loan Balance	11,555	11,555	7,991
Total impaired loans held to maturity, Loan Balance	14,024	14,024	10,235
Impaired loans, Related Allowance Recorded	372	372	442
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Impaired loans with a related allowance, Avg. Loan Balance	2,860	2,619	3,398
Impaired loans without a related allowance, Avg. Loan Balance	10,305	8,936	6,267
Total impaired loans held to maturity, Avg. Loan Balance	13,165	11,555	9,665
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract]
Impaired loans with a related allowance, Interest Income Recognized	7	16	12
Impaired loans without a related allowance, Interest Income Recognized	15	85	110
Total impaired loans held to maturity, Interest Income Recognized	22	101	122
Consumer
Impaired Financing Receivable, Unpaid Principal Balance [Abstract]
Impaired loans with a related allowance, Unpaid Contractual Balance	3,036	3,036	2,799
Impaired loans without a related allowance, Unpaid Contractual Balance	1,898	1,898	3,350
Total impaired loans held to maturity, Unpaid Contractual Balance	4,934	4,934	6,149
Impaired Financing Receivable, Recorded Investment [Abstract]
Impaired loans with a related allowance, Loan Balance	3,027	3,027	2,799
Impaired loans without a related allowance, Loan Balance	1,898	1,898	3,344
Total impaired loans held to maturity, Loan Balance	4,925	4,925	6,143
Impaired loans, Related Allowance Recorded	1,057	1,057	813
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Impaired loans with a related allowance, Avg. Loan Balance	3,136	2,845	4,053
Impaired loans without a related allowance, Avg. Loan Balance	2,025	2,431	1,870
Total impaired loans held to maturity, Avg. Loan Balance	5,161	5,276	5,923
Impaired Financing Receivable, Interest Income, Accrual Method [Abstract]
Impaired loans with a related allowance, Interest Income Recognized	5	16	19
Impaired loans without a related allowance, Interest Income Recognized	4	27	127
Total impaired loans held to maturity, Interest Income Recognized	$ 9	$ 43	$ 146