Note 29 - Segment Information - Detail Segment Information (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Net interest income $ 26,990 $ 26,717 $ 26,627 $ 25,902 $ 25,429 $ 24,833 $ 25,070 $ 24,795 $ 106,236 $ 100,127 $ 76,828
Provision for loan and lease losses 1,059 $ 1,412 $ 445 $ 1,410 1,777 $ 1,200 $ 850 $ 569 4,326 4,396 884
Net interest income after loan loss provision                 101,910 95,731 75,944
Fees for wealth management services                 36,690 36,894 36,774
Service charges on deposit accounts                 2,791 2,927 2,578
Loan servicing and other fees                 1,939 2,087 1,755
Net gain on sale of loans                 3,119 3,022 1,772
Net gain (loss) on sale of available for sale securities                 (77) 931 471
Net gain (loss) on sale of other real estate owned                 (76) 123 175
Insurance commissions                 3,722 3,745 1,099
Other operating income                 5,931 6,231 3,587
Total other income                 54,039 55,960 48,322
Salaries and wages                 47,411 44,575 37,113
Employee benefits                 9,548 10,205 7,340
Net loss on settlement of pension plan                 17,377
Occupancy and bank premises                 9,611 10,305 7,305
Amortization of intangible assets                 3,498 4,214 2,659
Professional fees                 3,659 3,353 3,017
Other operating expenses                 28,018 36,123 23,984
Total other expenses                 101,745 125,765 81,418
Segment profit                 54,204 25,926 42,848
Intersegment (revenues) expenses* [1]                
Pre-tax segment profit after eliminations                 $ 54,204 $ 25,926 $ 42,848
% of segment pre-tax profit after eliminations                 100.00% 100.00% 100.00%
Segment assets (dollars in millions) 3,421,530       3,030,997       $ 3,421,530 $ 3,030,997 $ 2,246,500
Banking [Member]                      
Net interest income                 106,233 100,124 76,825
Provision for loan and lease losses                 4,326 4,396 884
Net interest income after loan loss provision                 101,907 95,728 75,941
Fees for wealth management services                
Service charges on deposit accounts                 2,791 2,927 2,578
Loan servicing and other fees                 1,939 2,087 1,755
Net gain on sale of loans                 3,119 3,022 1,772
Net gain (loss) on sale of available for sale securities                 (77) 931 471
Net gain (loss) on sale of other real estate owned                 (76) 123 175
Insurance commissions                
Other operating income                 5,773 6,082 3,419
Total other income                 13,469 15,172 10,170
Salaries and wages                 32,321 30,391 24,612
Employee benefits                 6,257 7,298 4,306
Net loss on settlement of pension plan                 17,377
Occupancy and bank premises                 8,005 8,662 5,753
Amortization of intangible assets                 872 1,172 276
Professional fees                 3,516 3,227 2,923
Other operating expenses                 24,183 32,150 20,457
Total other expenses                 75,154 100,277 58,327
Segment profit                 40,222 10,623 27,784
Intersegment (revenues) expenses* [1]                 (396) (422) (372)
Pre-tax segment profit after eliminations                 $ 39,826 $ 10,201 $ 27,412
% of segment pre-tax profit after eliminations                 73.50% 39.30% 64.00%
Segment assets (dollars in millions) 3,377,100       2,983,200       $ 3,377,100 $ 2,983,200 $ 2,197,800
Wealth [Member]                      
Net interest income                 3 3 3
Provision for loan and lease losses                
Net interest income after loan loss provision                 3 3 3
Fees for wealth management services                 36,690 36,894 36,774
Service charges on deposit accounts                
Loan servicing and other fees                
Net gain on sale of loans                
Net gain (loss) on sale of available for sale securities                
Net gain (loss) on sale of other real estate owned                
Insurance commissions                 3,722 3,745 1,210
Other operating income                 158 149 168
Total other income                 40,570 40,788 38,152
Salaries and wages                 15,090 14,184 12,501
Employee benefits                 3,291 2,907 3,034
Net loss on settlement of pension plan                
Occupancy and bank premises                 1,606 1,643 1,552
Amortization of intangible assets                 2,626 2,655 2,383
Professional fees                 143 126 94
Other operating expenses                 3,835 3,973 3,527
Total other expenses                 26,591 25,488 23,091
Segment profit                 13,982 15,303 15,064
Intersegment (revenues) expenses* [1]                 396 422 372
Pre-tax segment profit after eliminations                 $ 14,378 $ 15,725 $ 15,436
% of segment pre-tax profit after eliminations                 26.50% 60.70% 36.00%
Segment assets (dollars in millions) $ 44,400       $ 47,800       $ 44,400 $ 47,800 $ 48,700
[1] Intersegment revenues consist of rental payments, deposit interest and management fees.