Investment Securities (Tables)

12 Months Ended

Dec. 31, 2020

Investments, Debt and Equity Securities [Abstract]

Held-to-Maturity Securities

A summary of the amortized cost, fair value, and allowance for credit losses on investment securities held-to-maturity is presented below:


	At December 31, 2020
(In thousands)	Amortized Cost (1)		Unrealized Gains		Unrealized Losses		Fair Value		Allowance (2)		Net Carrying Value
Agency CMO	$	91,622	$	1,785	$	(241)	$	93,166	$	—	$	91,622
Agency MBS	2,419,751		137,863		(84)		2,557,530		—		2,419,751
Agency CMBS	2,101,227		60,484		(2,213)		2,159,498		—		2,101,227
Municipal bonds and notes	739,507		60,371		(3)		799,875		299		739,208
CMBS	216,081		9,214		—		225,295		—		216,081
Held-to-maturity securities	$	5,568,188	$	269,717	$	(2,541)	$	5,835,364	$	299	$	5,567,889

	At December 31, 2019
(In thousands)	Amortized Cost (1)		Unrealized Gains		Unrealized Losses		Fair Value		Allowance (2)		Net Carrying Value
Agency CMO	$	167,443	$	1,123	$	(1,200)	$	167,366	$	—	$	167,443
Agency MBS	2,957,900		60,602		(8,733)		3,009,769		—		2,957,900
Agency CMBS	1,172,491		6,444		(5,615)		1,173,320		—		1,172,491
Municipal bonds and notes	740,431		32,709		(21)		773,119		—		740,431
CMBS	255,653		2,278		(852)		257,079		—		255,653
Held-to-maturity securities	$	5,293,918	$	103,156	$	(16,421)	$	5,380,653	$	—	$	5,293,918

Other than Temporary Impairment, Credit Losses Recognized in Earnings


	At December 31, 2020
(In thousands)	Amortized Cost		Fair Value
Due in one year or less	$	680	$	685
Due after one year through five years	4,458		4,711
Due after five through ten years	278,974		294,528
Due after ten years	5,284,076		5,535,440
Total held-to-maturity debt securities	$	5,568,188	$	5,835,364

For the maturity schedule above, investment securities which are not due at a single maturity date have been categorized based on the maturity date of the underlying collateral. Actual principal cash flows may differ from this maturity date presentation as borrowers have the right to repay obligations with or without prepayment penalties.

Debt Securities, Available-for-sale, Unrealized Loss Position, Fair Value

Fair Value and Unrealized Losses

The following tables provide information on fair value and unrealized losses for the individual available-for-sale securities with an unrealized loss, for which an allowance for credit losses on investment securities available-for-sale has not been recorded, aggregated by classification and length of time that the individual investment securities have been in a continuous unrealized loss position:


	At December 31, 2020
	Less Than Twelve Months				Twelve Months or Longer				Total
(Dollars in thousands)	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		# of Holdings	Fair Value		Unrealized Losses
Agency CMO	$	13,137	$	(49)	$	5,944	$	(49)	5	$	19,081	$	(98)
Agency MBS	33,742		(219)		4,561		(70)		30	38,303		(289)
Agency CMBS	376,330		(1,514)		—		—		8	376,330		(1,514)
CMBS	409,591		(5,486)		23,167		(337)		38	432,758		(5,823)
CLO	57,728		(265)		18,655		(45)		4	76,383		(310)
Corporate debt	4,100		(166)		9,020		(1,271)		3	13,120		(1,437)
Available-for-sale in unrealized loss position	$	894,628	$	(7,699)	$	61,347	$	(1,772)	88	$	955,975	$	(9,471)


	At December 31, 2019
	Less Than Twelve Months				Twelve Months or Longer				Total
(Dollars in thousands)	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		# of Holdings	Fair Value		Unrealized Losses
Agency CMO	$	36,447	$	(352)	$	32,288	$	(565)	9	$	68,735	$	(917)
Agency MBS	41,408		(193)		299,674		(3,842)		79	341,082		(4,035)
Agency CMBS	174,406		(1,137)		357,717		(5,798)		34	532,123		(6,935)
CMBS	355,260		(232)		7,480		(20)		29	362,740		(252)
CLO	—		—		43,232		(468)		2	43,232		(468)
Corporate debt	—		—		22,240		(1,245)		4	22,240		(1,245)
Available-for-sale in unrealized loss position	$	607,521	$	(1,914)	$	762,631	$	(11,938)	157	$	1,370,152	$	(13,852)

Summary of Debt Securities by Contractual Maturity

Contractual Maturities

The amortized cost and fair value of available-for-sale debt securities by contractual maturity are set forth below:


	At December 31, 2020
(In thousands)	Amortized Cost		Fair Value
Due in one year or less	$	—	$	—
Due after one year through five years	1,448		1,489
Due after five through ten years	252,601		248,958
Due after ten years	2,980,201		3,076,329
Total available-for-sale debt securities	$	3,234,250	$	3,326,776

For the maturity schedule above, investment securities which are not due at a single maturity date, have been categorized based on the maturity date of the underlying collateral. Actual principal cash flows may differ from this maturity date presentation as borrowers have the right to prepay obligations with or without prepayment penalties.