Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2022

Fair Value Disclosures [Abstract]

Valuation of Financial Instruments that are Marked-to-Market on Recurring Basis

The following table summarizes the valuation of our financial instruments that are marked to fair value on a recurring basis.

	Fair Value Measurements on a Recurring Basis
	March 31, 2022								December 31, 2021
(Dollars in thousands)	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Assets:
Trading investments	$	—	$	—	$	38,820	$	38,820	$	—	$	—	$	37,465	$	37,465
Available-for-sale investments	—		2,341,551		—		2,341,551		—		2,517,956		—		2,517,956
Derivative instruments	—		169		—		169		—		1,322		—		1,322
Total	$	—	$	2,341,720	$	38,820	$	2,380,540	$	—	$	2,519,278	$	37,465	$	2,556,743
Liabilities:
Derivative instruments	$	—	$	(263)	$	—	$	(263)	$	—	$	(252)	$	—	$	(252)
Total	$	—	$	(263)	$	—	$	(263)	$	—	$	(252)	$	—	$	(252)

Fair Values of Financial Assets and Liabilities, Including Derivative Financial Instruments

The following table summarizes the fair values of our financial assets and liabilities, including derivative financial instruments.

	March 31, 2022						December 31, 2021
(Dollars in thousands)	Fair Value		Carrying Value		Difference		Fair Value		Carrying Value		Difference
Earning assets:
Loans held for investment, net:
Private Education Loans	$	24,125,657	$	20,586,223	$	3,539,434	$	22,919,836	$	19,625,374	$	3,294,462
FFELP Loans	692,507		680,044		12,463		705,644		692,954		12,690
Credit Cards	27,581		25,408		2,173		25,037		22,955		2,082
Cash and cash equivalents	3,262,595		3,262,595		—		4,334,603		4,334,603		—
Trading investments	38,820		38,820		—		37,465		37,465		—
Available-for-sale investments	2,341,551		2,341,551		—		2,517,956		2,517,956		—
Accrued interest receivable	1,368,425		1,259,145		109,280		1,306,410		1,205,667		100,743
Tax indemnification receivable	8,155		8,155		—		8,047		8,047		—
Derivative instruments	169		169		—		1,322		1,322		—
Total earning assets	$	31,865,460	$	28,202,110	$	3,663,350	$	31,856,320	$	28,446,343	$	3,409,977
Interest-bearing liabilities:
Money-market and savings accounts	$	11,915,011	$	11,952,175	$	37,164	$	11,457,490	$	11,432,691	$	(24,799)
Certificates of deposit	9,171,506		9,239,829		68,323		9,451,528		9,394,001		(57,527)
Long-term borrowings	5,483,809		5,552,497		68,688		6,000,174		5,930,990		(69,184)
Accrued interest payable	61,379		61,379		—		46,600		46,600		—
Derivative instruments	263		263		—		252		252		—
Total interest-bearing liabilities	$	26,631,968	$	26,806,143	$	174,175	$	26,956,044	$	26,804,534	$	(151,510)
Excess of net asset fair value over carrying value					$	3,837,525					$	3,258,467