Note 4 - Investment Securities

12 Months Ended

Dec. 31, 2015

Investments, Debt and Equity Securities [Abstract]

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

4. Investment Securities

Investment Securities. The following tables reflect the amortized cost, gross unrealized gains, gross unrealized losses, and fair values of investment securities as of December 31, 2015, and December 31, 2014:

	As of December 31, 2015
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
	(In thousands)
Securities Available-for-Sale
U.S. treasury securities	$	284,678	$	5	$	395		284,288
U.S. government sponsored entities		150,000		-		1,840		148,160
Mortgage-backed securities		1,073,108		560		11,399		1,062,269
Collateralized mortgage obligations		63		-		27		36
Corporate debt securities		74,955		425		1,525		73,855
Mutual funds		6,000		-		167		5,833
Preferred stock of government sponsored entities		2,811		633		228		3,216
Other equity securities		4,108		4,929		342		8,695
Total securities available-for-sale	$	1,595,723	$	6,552	$	15,923	$	1,586,352

	As of December 31, 2014
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
	(In thousands)
Securities Available-for-Sale
U.S. treasury securities	$	664,206	$	63	$	265		664,004
Mortgage-backed securities		549,296		1,393		6,386		544,303
Collateralized mortgage obligations		79		-		34		45
Corporate debt securities		94,943		776		1,247		94,472
Mutual funds		6,000				134		5,866
Preferred stock of government sponsored entities		6,276		681		3,733		3,224
Other equity securities		3,608		3,413				7,021
Total securities available-for-sale	$	1,324,408	$	6,326	$	11,799	$	1,318,935

The amortized cost and fair value of investment securities at December 31, 2015, by contractual maturities are shown below. Actual maturities may differ from contractual maturities because borrowers may have the right to call or repay obligations with or without call or repayment penalties.  

	Securities Available-for-Sale
	Amortized Cost		Fair Value
	(In thousands)
Due in one year or less	$	184,963	$	184,956
Due after one year through five years		135,698		135,924
Due after five years through ten years		195,539		192,291
Due after ten years (1)		1,079,523		1,073,181
Total	$	1,595,723	$	1,586,352

(1) Equity securities are reported in this category

Proceeds from sales of mortgage-backed securities were $648.0 million and from repayments, maturities and calls of mortgage-backed securities were $101.2 million during 2015 compared to proceeds from sales of $698.5 million and proceeds of $69.7 million from repayments, maturities, and calls during 2014. Proceeds from sales of other investment securities were $385.2 million during 2015 compared to $160.5 million during 2014. Proceeds from maturities and calls of other investment securities were $165.0 during 2015 compared to $585.8 million during 2014. In 2015, gains of $2.4 million and losses of $1.9 million were realized on sales and calls of investment securities compared with gains of $18.0 million and losses of $10.5 million realized in 2014. In 2015, the Company recorded investment securities write-downs of $3.9 million compared to $0.8 million in 2014.

The temporarily impaired securities represent 92.0% of the fair value of investment securities as of December 31, 2015. Unrealized losses for securities with unrealized losses for less than twelve months represent 1.0%, and securities with unrealized losses for twelve months or more represent 3.3%, of the historical cost of these securities. Unrealized losses on these securities generally resulted from increases in interest rates or spreads subsequent to the date that these securities were purchased. At December 31, 2015, 7 issues of securities had unrealized losses for 12 months or longer and 47 issues of securities had unrealized losses of less than 12 months.

Total unrealized losses of $15.9 million at December 31, 2015, were primarily caused by increases in interest rates subsequent to the date that these securities were purchased or caused by the widening of credit and liquidity spreads since the dates of acquisition. The contractual terms of those investments do not permit the issuers to settle the security at a price less than the amortized cost of the investment.

At December 31, 2015, management believed the impairment was temporary and, accordingly, no impairment loss on debt securities has been recognized in our condensed consolidated statements of operations. The Company expects to recover the amortized cost basis of its debt securities, and has no intent to sell and believes it is more likely than not that it will not be required to sell available-for-sale debt securities that have declined below their cost before their anticipated recovery.

The tables below show the fair value and unrealized losses of the temporarily impaired securities in our investment securities portfolio as of December 31, 2015, and December 31, 2014:

	As of December 15, 2015
	Temporarily Impaired Securities
	Less than 12 months						12 months or longer						Total
	Fair Value		Unrealized Losses		No. of Issuances		Fair Value		Unrealized Losses		No. of Issuances		Fair Value		Unrealized Losses		No. of Issuances
	(Dollars in thousands)
Securities Available-for-Sale
U.S. treasury securities	$	224,289	$	395		5	$	-	$	-		-	$	224,289	$	395		5
U.S. government sponsored entities		148,160		1,840		3		-		-		-		148,160		1,840		3
Mortgage-backed securities		1,025,342		11,398		35		6		1		2		1,025,348		11,399		37
Collateralized mortgage obligations		-		-		-		36		27		1		36		27		1
Corporate debt securities		9,950		50		1		43,525		1,475		3		53,475		1,525		4
Mutual funds		-		-		-		5,833		167		1		5,833		167		1
Preferred stock of government sponsored entities		2,488		228		2		-		-		-		2,488		228		2
Other equity securities		158		342		1		-		-		-		158		342		1
Total securities available-for-sale	$	1,410,387	$	14,253		47	$	49,400	$	1,670		7	$	1,459,787	$	15,923		54

	As of December 31, 2014
	Temporarily Impaired Securities
	Less than 12 months						12 months or longer						Total
	Fair Value		Unrealized Losses		No. of Issuances		Fair Value		Unrealized Losses		No. of Issuances		Fair Value		Unrealized Losses		No. of Issuances
	(Dollars in thousands)
Securities Available-for-Sale
U.S. treasury securities	$	374,153	$	265		6	$	-	$	-		-	$	374,153	$	265		6
Mortgage-backed securities		-		-		-		425,090		6,386		16		425,090		6,386		16
Collateralized mortgage obligations		-		-		-		45		34		1		45		34		1
Corporate debt securities		-		-		-		63,753		1,247		4		63,753		1,247		4
Mutual funds		-		-		-		5,866		134		1		5,866		134		1
Preferred stock of government sponsored entities		2,448		3,733		2		-		-		-		2,448		3,733		2
Total securities available-for-sale	$	376,601	$	3,998		8	$	494,754	$	7,801		22	$	871,355	$	11,799		30

     Investment securities having a carrying value of $449.6 million at December 31, 2015, and $591.3 million at December 31, 2014, were pledged to secure public deposits, other borrowings, treasury tax and loan, Federal Home Loan Bank advances, securities sold under agreements to repurchase, and foreign exchange transactions.