INVESTMENTS (Tables)

9 Months Ended

Sep. 30, 2020

Investments, Debt and Equity Securities [Abstract]

Debt Securities, Available-for-sale

The following tables detail the amortized cost, allowance for credit losses and the estimated fair value of the Company's investments in available-for-sale and held-to-maturity debt securities. None of the Company's investments in debt securities are classified as trading.

	September 30, 2020
(Dollars in thousands)	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Allowance for Credit Losses		Fair Value
Available-for-Sale Debt Securities
CMO	$	417,162	$	11,455	$	84	$	—	$	428,533
FNMA MBS	1,393,291		61,809		192		—		1,454,908
FHLMC MBS	232,056		14,277		109		—		246,224
GNMA MBS	25,637		993		—		—		26,630
GSE agency notes	176,395		2,329		97		—		178,627
	$	2,244,541	$	90,863	$	482	$	—	$	2,334,922
Held-to-Maturity Debt Securities(1)
State and political subdivisions	$	113,115	$	4,504	$	—	$	7	$	117,612
Foreign bonds	501		—		—		—		501
	$	113,616	$	4,504	$	—	$	7	$	118,113

(1)Held-to-maturity securities transferred from available-for-sale are included in held-to-maturity at amortized cost basis at the time of transfer. The amortized cost of transferred held-to-maturity securities included net unrealized gains of $0.4 million at September 30, 2020, which are offset in Accumulated other comprehensive income. At the time of transfer, there was no allowance for credit loss on the available-for-sale securities. Subsequent to transfer, the securities were evaluated for credit loss. See Note 2 for updated Significant Accounting Policies on held-to-maturity debt securities.

	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

(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 transferred held-to-maturity securities included net unrealized gains of $0.6 million at December 31, 2019, which are offset in Accumulated other comprehensive income.

Debt Securities, Held-to-maturity

The following tables detail the amortized cost, allowance for credit losses and the estimated fair value of the Company's investments in available-for-sale and held-to-maturity debt securities. None of the Company's investments in debt securities are classified as trading.

	September 30, 2020
(Dollars in thousands)	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Allowance for Credit Losses		Fair Value
Available-for-Sale Debt Securities
CMO	$	417,162	$	11,455	$	84	$	—	$	428,533
FNMA MBS	1,393,291		61,809		192		—		1,454,908
FHLMC MBS	232,056		14,277		109		—		246,224
GNMA MBS	25,637		993		—		—		26,630
GSE agency notes	176,395		2,329		97		—		178,627
	$	2,244,541	$	90,863	$	482	$	—	$	2,334,922
Held-to-Maturity Debt Securities(1)
State and political subdivisions	$	113,115	$	4,504	$	—	$	7	$	117,612
Foreign bonds	501		—		—		—		501
	$	113,616	$	4,504	$	—	$	7	$	118,113

(1)Held-to-maturity securities transferred from available-for-sale are included in held-to-maturity at amortized cost basis at the time of transfer. The amortized cost of transferred held-to-maturity securities included net unrealized gains of $0.4 million at September 30, 2020, which are offset in Accumulated other comprehensive income. At the time of transfer, there was no allowance for credit loss on the available-for-sale securities. Subsequent to transfer, the securities were evaluated for credit loss. See Note 2 for updated Significant Accounting Policies on held-to-maturity debt securities.

	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

(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 transferred held-to-maturity securities included net unrealized gains of $0.6 million at December 31, 2019, which are offset in Accumulated other comprehensive income.

The following table presents the activity in the allowance for credit losses for debt securities held-to-maturity by major security type for the nine months ended September 30, 2020:

(Dollars in thousands)	State and political subdivisions		Foreign bonds
Allowance for credit losses:
Beginning balance	$	—	$	—
Impact of adoption ASC 326	8		—
Provision for credit losses	(1)		—
Charge-offs, net	—		—
Ending balance	$	7	$	—

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

The scheduled maturities of available-for-sale debt securities at September 30, 2020 and December 31, 2019 are presented in the table below:

	Available-for-Sale
	Amortized		Fair
(Dollars in thousands)	Cost		Value
September 30, 2020 (1)
Within one year	$	—	$	—
After one year but within five years	32,729		34,393
After five years but within ten years	219,962		233,169
After ten years	1,991,850		2,067,360
	$	2,244,541	$	2,334,922
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

(1)Actual maturities could differ from contractual maturities.

The scheduled maturities of held-to-maturity debt securities at September 30, 2020 and December 31, 2019 are presented in the table below:

	Held-to-Maturity
	Amortized		Fair
(Dollars in thousands)	Cost		Value
September 30, 2020 (1)
Within one year	$	1,152	$	1,168
After one year but within five years	1,549		1,567
After five years but within ten years	32,533		33,763
After ten years	78,382		81,615
	$	113,616	$	118,113
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

(1)Actual maturities could differ from contractual maturities.

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

For debt securities in an unrealized loss position and an allowance has not been recorded, the table below shows the 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 September 30, 2020.

	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	$	52,291	$	84	$	—	$	—	$	52,291	$	84
FNMA MBS	74,281		189		4,380		3		78,661		192
FHLMC MBS	5,196		109		—		—		5,196		109
GSE agency notes	25,751		97		—		—		25,751		97
Total	$	157,519	$	479	$	4,380	$	3	$	161,899	$	482

For debt securities in an unrealized loss position, the table below shows the 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
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
(Dollars in thousands)	Value		Loss		Value		Loss		Value		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	$	—

Held-to-maturity, Credit Quality Indicator

The following table summarizes the amortized cost of debt securities held-to-maturity as of September 30, 2020, aggregated by credit quality indicator:

(Dollars in thousands)	State and political subdivisions		Foreign bonds
A+ rated or higher	$	112,826	$	501
Not rated	289		—
Ending balance	$	113,115	$	501

Equity Investments

Equity Investments

The following tables detail the amortized cost, and the estimated fair value of the Company's equity investments, which are included in Other investments in the unaudited Consolidated Statements of Financial Condition.

	September 30, 2020
(Dollars in thousands)	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Fair Value
Equity Investments
Visa Class B shares(1)	$	618	$	185	$	—	$	803
Other equity investments(2)	11,279		—		1,646		9,633
	$	11,897	$	185	$	1,646	$	10,436

	December 31, 2019
(Dollars in thousands)	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss		Fair Value
Equity Investments
Visa Class B shares(1)	$	15,716	$	45,565	$	—	$	61,281
Other equity investments(2)	8,140		625		—		8,765
	$	23,856	$	46,190	$	—	$	70,046

(1)The Company recorded a net realized gain on sale of Visa Class B shares of $22.1 million during the nine months ended September 30, 2020, which is recorded in Realized gain on sale of equity investment in the Consolidated Statements of Income. The Company recorded unrealized gains on its remaining investment in Visa Class B shares of $0.2 million and $25.6 million during the nine months ended September 30, 2020 and 2019, respectively which is recorded in Unrealized gain on equity investment, net in the Consolidated Statements of Income.

(2)The Company recorded an impairment loss of $2.3 million in the investment of Spring EQ during the first quarter of 2020, which is recorded in Unrealized gain on equity investment, net in the Consolidated Statements of Income. There were no impairment losses recorded on the Company's equity investments during the nine months ended September 30, 2019. During the second quarter of 2020, the Company amended its agreement with Spring EQ in an exchange for additional equity interest. The additional equity interest in Spring EQ was valued at $2.4 million.