Investment Securities (Tables)

12 Months Ended

Dec. 31, 2019

Investments Schedule [Abstract]

Schedule of Amortized Cost and Estimated Fair Value of Available-for-Sale and Held-to-Maturity Investment Securities

The following tables detail the amortized cost and the estimated fair value of our investments in available-for-sale and held-to-maturity debt securities as well as our equity investments. None of our investments in debt securities are classified as trading.

	December 31, 2019
(Dollars in thousands)	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Fair Value
Available-for-Sale Debt Securities
CMO	$	336,194	$	4,578	$	542	$	340,230
FNMA MBS	1,219,522		25,717		2,786		1,242,453
FHLMC MBS	320,896		8,641		591		328,946
GNMA MBS	32,871		477		63		33,285
	$	1,909,483	$	39,413	$	3,982	$	1,944,914
Held-to-Maturity Debt Securities(1)
State and political subdivisions	$	131,600	$	3,023	$	—	$	134,623
Foreign bonds	2,001		1		—		2,002
	$	133,601	$	3,024	$	—	$	136,625
Equity Investments(2)
Visa Class B shares	$	15,716	$	45,565	$	—	$	61,281
Other equity investments	8,140		625		—		8,765
	$	23,856	$	46,190	$	—	$	70,046

(1)Held-to-maturity securities transferred from available-for-sale are included in held-to-maturity at fair value at the time of transfer. The amortized cost of held-to-maturity securities included net unrealized gains of $0.6 million at December 31, 2019, related to securities transferred, which are offset in Accumulated other comprehensive loss, net of tax.

(2)Equity investments are included in Other investments in the audited Consolidated Statements of Financial Condition.

	December 31, 2018
(Dollars in thousands)	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Fair Value
Available-for-Sale Debt Securities
CMO	$	376,867	$	1,721	$	6,838	$	371,750
FNMA MBS	655,485		1,526		12,938		644,073
FHLMC MBS	155,758		558		2,394		153,922
GNMA MBS	36,117		97		880		35,334
	$	1,224,227	$	3,902	$	23,050	$	1,205,079
Held-to-Maturity Debt Securities(1)
State and political subdivisions	$	149,950	$	275	$	794	$	149,431
Equity Investments(2)
Visa Class B shares	$	13,918	$	20,015	$	—	$	33,933
Other equity investments	3,300		—		—		3,300
	$	17,218	$	20,015	$	—	$	37,233

(1)Held-to-maturity securities transferred from available-for-sale are included in held-to-maturity at fair value at the time of transfer. The amortized cost of held-to-maturity securities included net unrealized gains of $1.0 million at December 31, 2018, related to securities transferred, which are offset in Accumulated other comprehensive loss, net of tax.

(2)Equity investments are included in Other investments in the audited Consolidated Statements of Financial Condition.

Schedule of Maturities of Investment Securities Available-for-Sale and Held-to-Maturity

The scheduled maturities of our available-for-sale and held-to-maturity at December 31, 2019 and December 31, 2018 are presented in the table below:

	Available-for-Sale
(Dollars in thousands)	Amortized Cost		Fair Value
December 31, 2019 (1)
Within one year	$	—	$	—
After one year but within five years	22,136		22,207
After five years but within ten years	194,197		194,376
After ten years	1,693,150		1,728,331
	$	1,909,483	$	1,944,914
December 31, 2018 (1)
Within one year	$	—	$	—
After one year but within five years	19,714		19,423
After five years but within ten years	170,118		163,731
After ten years	1,034,395		1,021,925
	$	1,224,227	$	1,205,079
	Held-to-Maturity
(Dollars in thousands)	Amortized Cost		Fair Value
December 31, 2019 (1)
Within one year	$	2,649	$	2,653
After one year but within five years	4,239		4,270
After five years but within ten years	35,288		35,967
After ten years	91,425		93,735
	$	133,601	$	136,625
December 31, 2018 (1)
Within one year	$	1,018	$	1,016
After one year but within five years	6,703		6,701
After five years but within ten years	29,613		29,547
After ten years	112,616		112,167
	$	149,950	$	149,431

(1)Actual maturities could differ from contractual maturities.

Schedule of Investment Securities' Gross Unrealized Losses and Fair Value by Investment Category

For those debt securities with unrealized losses, the table below shows our gross unrealized losses and fair value by investment category and length of time that individual debt securities were in a continuous unrealized loss position at December 31, 2019. 

	Duration of Unrealized Loss Position
	Less than 12 months				12 months or longer				Total
(Dollars in thousands)	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Available-for-sale debt securities:
CMO	$	47,376	$	481	$	7,999	$	61	$	55,375	$	542
FNMA MBS	310,312		2,681		6,522		105		316,834		2,786
FHLMC MBS	35,354		541		2,836		50		38,190		591
GNMA MBS	1,847		4		5,742		59		7,589		63
Total temporarily impaired investments	$	394,889	$	3,707	$	23,099	$	275	$	417,988	$	3,982
Held-to-maturity debt securities:
State and political subdivisions(1)	$	523	$	—	$	—	$	—	$	523	$	—

(1)State and political subdivisions with an unrealized loss position of less than twelve months had an unrealized loss of less than $1 thousand at December 31, 2019.

For debt securities with unrealized losses, the table below shows our gross unrealized losses and fair value by investment category and length of time that individual debt securities were in a continuous unrealized loss position at December 31, 2018.

	Duration of Unrealized Loss Position
	Less than 12 months				12 months or longer				Total
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
(Dollars in thousands)	Value		Loss		Value		Loss		Value		Loss
Available-for-sale debt securities:
CMO	$	17,143	$	40	$	212,208	$	6,798	$	229,351	$	6,838
FNMA MBS	34,214		162		407,638		12,776		441,852		12,938
FHLMC MBS	16,025		21		76,469		2,373		92,494		2,394
GNMA MBS	5,837		79		21,805		801		27,642		880
Total temporarily impaired investments	$	73,219	$	302	$	718,120	$	22,748	$	791,339	$	23,050
Held-to-maturity debt securities:
State and political subdivisions	$	91,228	$	155	$	58,203	$	639	$	149,431	$	794