Note 17 - Revenue from Contracts with Customers - Summary of Revenue (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Fees and service charges on deposit accounts										$ 27,985		$ 25,649		$ 25,486
Noninterest income, not in-scope(3)	[1]									3,722		10,648		7,884
Total non-interest income		$ 10,795	$ 7,835	$ 7,767	$ 5,310	$ 10,466	$ 12,961	$ 6,152	$ 6,718	31,707	[2]	36,297	[2]	33,370	[2]
Fees and Services Charges on Deposit Account [Member]
Fees and service charges on deposit accounts	[2]									8,387		9,173		9,082
Wealth Management Fees [Member]
Fees and service charges on deposit accounts	[2]									5,905		3,065		3,590
Other Service Fees [Member]
Fees and service charges on deposit accounts	[2],[3]									$ 13,693		$ 13,411		$ 12,814

[1] These amounts primarily represent revenue from contracts with customers that are out of the scope of ASC 606.

[2] There were no adjustments to the Company's financial statements recorded as a result of the adoption of ASC 606. For comparability, the Company has adjusted prior period amounts to conform to the periods presentation.

[3] Other service fees comprise of fees related to letters of credit, wire fees, fees on foreign exchange transactions and other immaterial individual revenue streams.