Note 3 - Securities

12 Months Ended

Dec. 31, 2014

Investments, Debt and Equity Securities [Abstract]

Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]

Note 3: Securities

The amortized cost and fair value of securities available for sale, with gross unrealized gains and losses, follows:

	December 31, 2014
Available for sale:	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. Government agencies and corporations		197,740		973		4,494		194,219
States and political subdivisions		18,529		851		---		19,380
Mortgage-backed securities		1,830		184		---		2,014
Corporate debt securities		6,991		140		27		7,104
Other securities		189		---		62		127
Total securities available for sale	$	225,279	$	2,148	$	4,583	$	222,844

	December 31, 2013
Available for sale:	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. Government agencies and corporations		169,818		199		22,163		147,854
States and political subdivisions		22,830		746		120		23,456
Mortgage-backed securities		2,627		213		----		2,840
Corporate debt securities		7,804		97		506		7,395
Other securities		189		---		22		167
Total securities available for sale	$	203,268	$	1,255	$	22,811	$	181,712

The amortized cost and fair value of single maturity securities available for sale at December 31, 2014, by contractual maturity, are shown below. Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Mortgage-backed securities included in these totals are categorized by final maturity at December 31, 2014.

	December 31, 2014
	Amortized Cost		Fair Value
Due in one year or less	$	1,864	$	1,899
Due after one year through five years		30,930		31,171
Due after five years through ten years		30,161		30,156
Due after ten years		162,135		159,491
No maturity		189		127
	$	225,279	$	222,844

The Company holds restricted stock with the Federal Home Loan Bank and the Federal Reserve. Required ownership amounts are determined by the correspondent banks and the Company purchases stock from or sells stock back to the correspondents based on their calculations. The stock is held by member institutions only and is not actively traded. The Company held restricted stock of $1,089 as of December 31, 2014 and $1,414 as of December 31, 2013.

The amortized cost and fair value of securities held to maturity, with gross unrealized gains and losses, follows:

	December 31, 2014
Held to maturity:	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. Government agencies and corporations	$	18,922	$	350	$	245	$	19,027
States and political subdivisions		140,702		6,823		727		146,798
Mortgage-backed securities		415		51		---		466
Corporate debt securities		1,413		1		2		1,412
Total securities held to maturity	$	161,452	$	7,225	$	974	$	167,703

	December 31, 2013
Held to maturity:	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
U.S. Government agencies and corporations	$	13,973	$	280	$	1,448	$	12,805
States and political subdivisions		149,490		2,971		6,502		145,959
Mortgage-backed securities		520		53		---		573
Total securities held to maturity	$	163,983	$	3,304	$	7,950	$	159,337

The amortized cost and fair value of single maturity securities held to maturity at December 31, 2014, by contractual maturity, are shown below. Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Mortgage-backed securities included in these totals are categorized by final maturity at December 31, 2014.

	December 31, 2014
	Amortized Cost		Fair Value
Due in one year or less	$	1,637	$	1,650
Due after one year through five years		4,987		5,262
Due after five years through ten years		24,052		25,181
Due after ten years		130,776		135,610
	$	161,452	$	167,703

Information pertaining to securities with gross unrealized losses at December 31, 2014 and 2013 aggregated by investment category and length of time that individual securities have been in a continuous loss position, follows:

	December 31, 2014
	Less Than 12 Months				12 Months or More
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
U. S. Government agencies and corporations	$	6,964	$	30	$	156,149	$	4,709
State and political subdivisions		1,222		35		19,818		692
Corporate debt securities		450		2		1,948		27
Other securities		---		---		127		62
Total temporarily impaired securities	$	8,636	$	67	$	178,042	$	5,490

	December 31, 2013
	Less Than 12 Months				12 Months or More
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
U. S. Government agencies and corporations	$	138,324	$	20,400	$	15,796	$	3,211
State and political subdivisions		58,013		6,131		2,697		491
Corporate debt securities		5,511		506		---		---
Other securities		167		22		---		---
Total temporarily impaired securities	$	202,015	$	27,059	$	18,493	$	3,702

At December 31, 2014, the Company had 205 securities with a fair value of $186,678 which had total unrealized losses of $5,557. The Company has made the determination that these securities are temporarily impaired at December 31, 2014 for the following reasons:

U.S. Government agencies and corporations. The unrealized losses in this category of investments were caused by interest rate fluctuations. The contractual terms of the investments do not permit the issuer to settle the securities at a price less than the cost basis of each investment. Because the Company does not intend to sell any of the investments and the accounting standard of “more likely than not” has not been met for the Company to be required to sell any of these investments before recovery of its amortized cost basis, which may be maturity, the Company does not consider these investments to be other-than-temporarily impaired.

State and political subdivisions. This category’s unrealized losses are primarily the result of interest rate fluctuations and also a certain few ratings downgrades brought about by the impact of the economic downturn on states and political subdivisions. The securities remain investment grade and the Company’s analysis did not indicate the existence of a credit loss. The contractual terms of the investments do not permit the issuer to settle the securities at a price less than the cost basis of each investment. Because the Company does not intend to sell any of the investments and the accounting standard of “more likely than not” has not been met for the Company to be required to sell any of the investments before recovery of its amortized cost basis, which may be maturity, the Company does not consider these investments to be other-than-temporarily impaired.

Corporate debt securities. The Company’s unrealized losses in corporate debt securities are related to both interest rate fluctuations and ratings downgrades for a limited number of securities. The securities remain investment grade and the Company’s analysis did not indicate the existence of a credit loss. The contractual terms of the investments do not permit the issuer to settle the securities at a price less than the cost basis of each investment. Because the Company does not intend to sell any of the investments before recovery of its amortized cost basis, which may be maturity, the Company does not consider these investments to be other-than-temporarily impaired.

Other. The Company holds an investment in a small amount of community bank stock. The value of the investment has been negatively affected by market conditions. Because the Company does not intend to sell the investment before recovery of amortized cost basis, the Company does not consider these investments to be other-than-temporarily impaired.

At December 31, 2013, the Company had 286 securities with a fair value of $220,508 which were temporarily impaired. The total unrealized loss on these securities, which was attributed to interest rate fluctuations, was $30,761. Because the Company had the ability and intent to hold the securities until maturity or until the cost was recovered, the losses associated with the securities were not considered other than temporary at December 31, 2013.

At December 31, 2014 and 2013, securities with a carrying value of $157,951 and $139,873, respectively, were pledged to secure trust deposits and for other purposes as required or permitted by law.

As a member of the Federal Reserve and the Federal Home Loan Bank (“FHLB”) of Atlanta, NBB is required to maintain certain minimum investments in the common stock of those entities. Required levels of investment are based upon NBB’s capital and a percentage of qualifying assets. In addition, NBB is eligible to borrow from the FHLB with borrowings collateralized by qualifying assets, primarily residential mortgage loans totaling approximately $437,847, and NBB’s capital stock investment in the FHLB. Redemption of FHLB stock is subject to certain limitations and conditions. At its discretion, the FHLB may declare dividends on the stock. Management reviews for impairment based upon the ultimate recoverability of the cost basis in the FHLB stock.