Note 11 - Fair Value Measurements - Financial Assets and Liabilities Measured On a Non-recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Mar. 31, 2017		Mar. 31, 2016		Dec. 31, 2016		Dec. 31, 2015
Total at Fair Value	$ 38,437				$ 37,981
Total Losses	494		$ 238		1,307		$ 2,507
Fair Value, Inputs, Level 1 [Member]
Total at Fair Value
Fair Value, Inputs, Level 2 [Member]
Total at Fair Value	3,280				6,006
Fair Value, Inputs, Level 3 [Member]
Total at Fair Value	35,157				31,975
Impaired Loans [Member]
Total at Fair Value	27,366				23,936
Total Losses	270				322		1,550
Impaired Loans [Member] | Fair Value, Inputs, Level 1 [Member]
Total at Fair Value
Impaired Loans [Member] | Fair Value, Inputs, Level 2 [Member]
Total at Fair Value
Impaired Loans [Member] | Fair Value, Inputs, Level 3 [Member]
Total at Fair Value	27,366				23,936
Impaired Loans [Member] | Commercial Portfolio Segment [Member]
Total at Fair Value	917				2,813
Total Losses	20				322		806
Impaired Loans [Member] | Commercial Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member]
Total at Fair Value
Impaired Loans [Member] | Commercial Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member]
Total at Fair Value
Impaired Loans [Member] | Commercial Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Total at Fair Value	917				2,813
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member]
Total at Fair Value	14,996				9,444
Total Losses	250						598
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member]
Total at Fair Value
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member]
Total at Fair Value
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Total at Fair Value	14,996				9,444
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member]
Total at Fair Value	11,453				11,679
Total Losses							146
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member]
Total at Fair Value
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member]
Total at Fair Value
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Total at Fair Value	11,453				11,679
Other Real Estate Owned [Member]
Total at Fair Value	7,602	[1]			10,378	[2]
Total Losses	37	[1]	128	[1]	9	[2]	404	[2]
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 1 [Member]
Total at Fair Value		[1]				[2]
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 2 [Member]
Total at Fair Value	3,280	[1]			6,006	[2]
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 3 [Member]
Total at Fair Value	4,322	[1]			4,372	[2]
Equity Investments [Member]
Total at Fair Value	3,469				3,667
Total Losses	187		$ 110		976		$ 553
Equity Investments [Member] | Fair Value, Inputs, Level 1 [Member]
Total at Fair Value
Equity Investments [Member] | Fair Value, Inputs, Level 2 [Member]
Total at Fair Value
Equity Investments [Member] | Fair Value, Inputs, Level 3 [Member]
Total at Fair Value	$ 3,469				$ 3,667

[1] Other real estate owned balance of $19.9 million in the Consolidated Balance Sheets is net of estimated disposal costs.

[2] Other real estate owned balance of $20.1 million in the Consolidated Balance Sheets is net of estimated disposal costs.