SECURITIES (Tables)

3 Months Ended

Mar. 31, 2017

SECURITIES [Abstract]

Amortized Cost And Estimated Fair Values Of Available-For-Sale Securities

		March 31, 2017
			Gross	Gross	Estimated
		Amortized	Unrealized	Unrealized	Fair
		Cost	Gains	Losses	Value
	(In thousands)
U.S. Government agencies		$   1,823,294	$           861	$        5,975	$   1,818,180
U.S. Government agency issued residential mortgage-backed securities		167,986	1,389	1,833	167,542
U.S. Government agency issued commercial mortgage-backed securities		169,996	1,510	1,424	170,082
Obligations of states and political subdivisions		337,595	16,193	1,464	352,324
FHLB and other securities		32,531	228	-	32,759
Total		$   2,531,402	$      20,181	$      10,696	$   2,540,887

		December 31, 2016
			Gross	Gross	Estimated
		Amortized	Unrealized	Unrealized	Fair
		Cost	Gains	Losses	Value
	(In thousands)
U.S. Government agencies		$   1,794,231	$        1,261	$        6,065	$   1,789,427
U.S. Government agency issued residential  mortgage-backed securities		176,476	1,665	1,898	176,243
U.S. Government agency issued commercial mortgage-backed securities		171,840	1,648	1,209	172,279
Obligations of states and political subdivisions		346,609	15,547	2,151	360,005
FHLB and other securities		32,436	1,286	-	33,722
Total		$   2,521,592	$      21,407	$      11,323	$   2,531,676

	March 31, 2016
		Gross	Gross	Estimated
	Amortized	Unrealized	Unrealized	Fair
	Cost	Gains	Losses	Value
	(In thousands)
U.S. Government agencies	$   1,190,199	$        5,974	$               6	$   1,196,167
U.S. Government agency issued residential mortgage-backed securities	187,410	2,582	251	189,741
U.S. Government agency issued commercial mortgage-backed securities	204,246	3,719	57	207,908
Obligations of states and political subdivisions	384,326	24,219	8	408,537
FHLB and other securities	13,142	878	-	14,020
Total	$   1,979,323	$      37,372	$           322	$   2,016,373

Amortized Cost And Estimated Fair Value Of Available-For-Sale Securities By Contractual Maturity

	March 31, 2017
		Estimated	Weighted
	Amortized	Fair	Average
	Cost	Value	Yield
	(Dollars in thousands)
Maturing in one year or less	$      569,032	$      569,120	1.05	%
Maturing after one year through five years	1,347,399	1,341,746	1.37
Maturing after five years through ten years	45,459	47,804	5.90
Maturing after ten years	231,530	244,593	5.47
Mortgage-backed securities	337,982	337,624	2.18
Total	$   2,531,402	$   2,540,887

Temporarily Impaired Available-For-Sale Securities With Continuous Unrealized Loss Positions

	March 31, 2017
	Continuous Unrealized Loss Position
	Less Than 12 Months		12 Months or Longer		Total
	Fair	Unrealized	Fair	Unrealized	Fair	Unrealized
	Value	Losses	Value	Losses	Value	Losses
	(In thousands)
U.S. Government agencies	$  1,319,456	$        5,975	$                -	$                -	$  1,319,456	$        5,975
U.S. Government agency issued residential mortgage-backed securities	88,596	1,751	5,578	82	94,174	1,833
U.S. Government agency issued commercial mortgage-backed securities	128,763	1,295	13,662	129	142,425	1,424
Obligations of states and political subdivisions	25,727	1,464	-	-	25,727	1,464
Total	$  1,562,542	$      10,485	$      19,240	$           211	$  1,581,782	$      10,696

	December 31, 2016
	Continuous Unrealized Loss Position
	Less Than 12 Months		12 Months or Longer		Total
	Fair	Unrealized	Fair	Unrealized	Fair	Unrealized
	Value	Losses	Value	Losses	Value	Losses
	(In thousands)
U.S. Government agencies	$  1,082,573	$        6,065	$                -	$                -	$  1,082,573	$        6,065
U.S. Government agency issued residential mortgage-backed securities	71,599	1,783	15,375	115	86,974	1,898
U.S. Government agency issued commercial mortgage-backed securities	129,940	1,084	14,385	125	144,325	1,209
Obligations of states and political subdivisions	46,798	2,151	-	-	46,798	2,151
Total	$  1,330,910	$      11,083	$      29,760	$           240	$  1,360,670	$      11,323