Investments (Tables)

3 Months Ended

Mar. 31, 2019

Investments [Abstract]

Aggregate Carrying And Approximate Market Values Of Available-For-Sale Securities

	March 31, 2019								December 31, 2018
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Securities available-for-sale:
U.S. Treasuries and U.S.
government agencies	$	2,277	$	23	$	—	$	2,300	$	5,713	$	20	$	—	$	5,733
Obligations of states and
political subdivisions	123,293		2,632		285		125,640		128,089		1,033		1,052		128,070
Mortgage-backed securities:
U.S. government agencies	590,773		4,871		6,946		588,698		561,799		1,950		12,991		550,758
Private label	11,787		328		—		12,115		11,948		95		—		12,043
Trust preferred securities	4,776		31		569		4,238		4,774		25		—		4,799
Corporate securities	16,787		93		1		16,879		16,795		30		167		16,658
Total Debt Securities	749,693		7,978		7,801		749,870		729,118		3,153		14,210		718,061
Certificates of deposit held for investment	3,735		—		—		3,735		3,735		—		—		3,735
Investment funds	1,526		—		50		1,476		1,525		—		67		1,458
Total Securities
Available-for-Sale	$	754,954	$	7,978	$	7,851	$	755,081	$	734,378	$	3,153	$	14,277	$	723,254

Aggregate Carrying And Approximate Market Values Of Held-To-Maturity Securities

Securities held-to-maturity:
Mortgage-backed securities:
U.S. government agencies	$	55,326	$	858	$	99	$	56,085	$	56,827	$	173	$	294	$	56,706
Trust preferred securities	—		—		—		—		4,000		—		—		4,000
Total Securities
Held-to-Maturity	$	55,326	$	858	$	99	$	56,085	$	60,827	$	173	$	294	$	60,706

Gross Unrealized Losses And Fair Value Of Investments

	March 31, 2019
	Less Than Twelve Months				Twelve Months or Greater				Total
	Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss
Securities available-for-sale:
Obligations of states and political subdivisions	$	832	$	3	$	20,922	$	282	$	21,754	$	285
Mortgage-backed securities:
U.S. Government agencies	5,654		2		343,082		6,944		348,736		6,946
Trust preferred securities	3,972		569		—		—		3,972		569
Corporate securities	1,020		1		—		—		1,020		1
Investment funds	1,500		50		—		—		1,500		50
Total available-for-sale	$	12,978	$	625	$	364,004	$	7,226	$	376,982	$	7,851
Securities held-to-maturity:
Mortgage-backed securities:
U.S. Government agencies	$	—	$	—	$	5,896	$	99	$	5,896	$	99
Total held-to-maturity	$	—	$	—	$	5,896	$	99	$	5,896	$	99

	December 31, 2018
	Less Than Twelve Months				Twelve Months or Greater				Total
	Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss		Estimated Fair Value		Unrealized Loss
Securities available-for-sale:
Obligations of states and political subdivisions	$	11,837	$	272	$	22,068	$	780	$	33,905	$	1,052
Mortgage-backed securities:
U.S. Government agencies	84,975		1,593		282,560		11,398		367,535		12,991
Corporate securities	12,995		167		—		—		12,995		167
Investment funds	1,500		67		—		—		1,500		67
Total available-for-sale	$	111,307	$	2,099	$	304,628	$	12,178	$	415,935	$	14,277
Securities held-to-maturity:
Mortgage-backed securities
U.S. Government agencies	$	28,274	$	126	$	5,960	$	168	$	34,234	$	294
Total held-to-maturity	$	28,274	$	126	$	5,960	$	168	$	34,234	$	294

Amortized Cost And Estimated Fair Value Of Debt Securities By Contractual Maturity

The amortized cost and estimated fair value of debt securities at March 31, 2019, by contractual maturity, are shown in the following table (in thousands).  Expected maturities will differ from contractual maturities because the issuers of the securities may have the right to prepay obligations without prepayment penalties.  Mortgage-backed securities have been allocated to their respective maturity groupings based on their contractual maturity.

	Amortized Cost		Estimated Fair Value
Available-for-Sale Debt Securities
Due in one year or less	$	3,238	$	3,241
Due after one year through five years	18,566		18,776
Due after five years through ten years	156,128		156,585
Due after ten years	571,761		571,268
Total	$	749,693	$	749,870
Held-to-Maturity Debt Securities
Due in one year or less	$	—	$	—
Due after one year through five years	—		—
Due after five years through ten years	4,929		5,230
Due after ten years	50,397		50,855
Total	$	55,326	$	56,085

Gross Gains And Losses Realized

	Three months ended March 31,
	2019			2018
Gross unrealized gains recognized on securities still held	$	143		$	283
Gross unrealized losses recognized on securities still held	(68		)	(3		)
Net unrealized gains (losses) recognized on securities still held	$	75		$	280
Gross realized gains on securities sold	$	89		$	—
Gross realized losses on securities sold	(1		)	—
Net investment security gains	$	88		$	—