Note 12 - Minimum Regulatory Capital Requirement (Tables)

12 Months Ended

Dec. 31, 2016

Notes Tables

Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block]

	Actual					Minimum Capital Requirement (1)					Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions
	Amount		Ratio			Amount		Ratio			Amount		Ratio
December 31, 201 6
Total capital (to risk weighted assets)
NBI consolidated	$	191,006		26.575	%	$	57,499		8.625	%		N/A		N/A
NBB		188,095		26.296	%		57,224		8.625	%	$	71,529		10.000	%
Tier 1 capital (to risk weighted assets)
NBI consolidated	$	182,706		25.420	%	$	43,124		6.625	%		N/A		N/A
NBB		179,795		25.136	%		42,918		6.625	%	$	57,224		8.000	%
Common Equity Tier 1 capital (to risk weighted assets)
NBI consolidated	$	182,706		25.420	%	$	32,343		5.125	%		N/A		N/A
NBB		179,795		25.136	%		32,188		5.125	%	$	46,494		6.500	%
Tier 1 capital (to average assets)
NBI consolidated	$	182,706		15.121	%	$	48,333		4.000	%		N/A		N/A
NBB		179,795		14.964	%		48,060		4.000	%	$	60,075		5.000	%

	Actual					Minimum Capital Requirement					Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions
	Amount		Ratio			Amount		Ratio			Amount		Ratio
December 31, 2015
Total capital (to risk weighted assets)
NBI consolidated	$	184,054		25.527	%	$	57,681		8.000	%		N/A		N/A
NBB		181,926		25.300	%		57,526		8.000	%	$	71,908		10.000	%
Tier 1 capital (to risk weighted assets)
NBI consolidated	$	175,757		24.376	%	$	43,261		6.000	%		N/A		N/A
NBB		173,629		24.146	%		43,145		6.000	%	$	57,526		8.000	%
Common Equity Tier 1 capital (to risk weighted assets)
NBI consolidated	$	175,757		24.376	%	$	32,446		4.500	%		N/A		N/A
NBB		173,629		24.146	%		32,358		4.500	%	$	46,740		6.500	%
Tier 1 capital (to average assets)
NBI consolidated	$	175,757		15.088	%	$	46,594		4.000	%		N/A		N/A
NBB		173,629		14.888	%		46,648		4.000	%	$	58,310		5.000	%