Securities (Tables)

6 Months Ended

Jun. 30, 2011

Securities

Summary Of Available-For-Sale And Held-To-Maturity Securities

	June 30, 2011
	Amortized Cost Basis		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses			Estimated Fair Value
Securities available-for-sale:
U. S. Treasury securities	$	15,198	$	271	$	—		$	15,469
Obligations of U.S. government sponsored-enterprises and agencies		251,648		7,585		—			259,233
Obligations of states and political subdivisions		555,118		28,944		(489	)		583,573
Corporate bonds and other		41,164		4,058		—			45,222
Mortgage-backed securities		710,781		26,259		(545	)		736,495
Total securities available-for-sale	$	1,573,909	$	67,117	$	(1,034	)	$	1,639,992
Securities held-to-maturity:
Obligations of states and political subdivisions	$	6,201	$	76	$	—		$	6,277
Mortgage-backed securities		462		17		—			479
Total debt securities held-to-maturity	$	6,663	$	93	$	—		$	6,756

	December 31, 2010
	Amortized Cost Basis		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses			Estimated Fair Value
Securities available-for-sale:
U. S. Treasury securities	$	15,253	$	263	$	—		$	15,516
Obligations of U.S. government sponsored-enterprises and agencies		270,706		8,542		—			279,248
Obligations of states and political subdivisions		543,074		12,695		(5,861	)		549,908
Corporate bonds and other		56,710		4,118		—			60,828
Mortgage-backed securities		611,275		22,283		(1,880	)		631,678
Total securities available-for-sale	$	1,497,018	$	47,901	$	(7,741	)	$	1,537,178
Securities held-to-maturity:
Obligations of states and political subdivisions	$	8,549	$	160	$	—		$	8,709
Mortgage-backed securities		515		16		—			531
Total debt securities held-to-maturity	$	9,064	$	176	$	—		$	9,240

Amortized Cost And Estimated Fair Value Of Debt Securities

	Held-to-Maturity				Available-for-Sale
	Amortized Cost Basis		Estimated Fair Value		Amortized Cost Basis		Estimated Fair Value
Due within one year	$	5,851	$	5,911	$	129,079	$	131,636
Due after one year through five years		350		366		377,211		393,703
Due after five years through ten years		—		—		323,650		344,175
Due after ten years		—		—		33,188		33,983
Mortgage-backed securities		462		479		710,781		736,495
Total	$	6,663	$	6,756	$	1,573,909	$	1,639,992

Continuous Unrealized-Loss Position Of Available-For-Sale And Held-To-Maturity Securities

	Less than 12 Months				12 Months or Longer				Total
June 30, 2011	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Obligations of states and political subdivisions	$	24,290	$	467	$	1,748	$	22	$	26,038	$	489
Mortgage-backed securities		28,072		545		—		—		28,072		545
Total	$	52,362	$	1,012	$	1,748	$	22	$	54,110	$	1,034
	Less than 12 Months				12 Months or Longer				Total
December 31, 2010	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Obligations of states and political subdivisions	$	164,437	$	5,665	$	2,070	$	196	$	166,507	$	5,861
Mortgage-backed securities		110,591		1,880		—		—		110,591		1,880
Total	$	275,028	$	7,545	$	2,070	$	196	$	277,098	$	7,741