Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2020

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
	September 30, 2020								December 31, 2019
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Assets
Available-for-sale investments	$	—	$	2,018,388	$	72,319	$	2,090,707	$	—	$	487,669	$	—	$	487,669
Derivative instruments	—		541		—		541		—		715		—		715
Total	$	—	$	2,018,929	$	72,319	$	2,091,248	$	—	$	488,384	$	—	$	488,384
Liabilities
Derivative instruments	$	—	$	—	$	—	$	—	$	—	$	(1,164)	$	—	$	(1,164)
Total	$	—	$	—	$	—	$	—	$	—	$	(1,164)	$	—	$	(1,164)

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.

	September 30, 2020						December 31, 2019
	Fair Value		Carrying Value		Difference		Fair Value		Carrying Value		Difference
Earning assets:
Loans held for investment, net:
Private Education Loans	$	24,328,972	$	20,955,922	$	3,373,050	$	24,988,941	$	22,896,515	$	2,092,426
FFELP Loans	756,739		743,220		13,519		795,055		783,816		11,239
Personal Loans	—		—		—		1,047,119		983,643		63,476
Credit Cards	10,970		10,629		341		3,818		3,818		—
Cash and cash equivalents	4,351,045		4,351,045		—		5,563,877		5,563,877		—
Trading investments	14,651		14,651		—		—		—		—
Available-for-sale investments	2,090,707		2,090,707		—		487,669		487,669		—
Accrued interest receivable	1,567,103		1,472,602		94,501		1,491,471		1,392,725		98,746
Tax indemnification receivable	28,256		28,256		—		27,558		27,558		—
Derivative instruments	541		541		—		715		715		—
Total earning assets	$	33,148,984	$	29,667,573	$	3,481,411	$	34,406,223	$	32,140,336	$	2,265,887
Interest-bearing liabilities:
Money-market and savings accounts	$	10,944,983	$	10,870,551	$	(74,432)	$	10,363,691	$	10,335,163	$	(28,528)
Certificates of deposit	12,464,852		12,238,887		(225,965)		14,065,007		13,947,743		(117,264)
Short-term borrowings	—		—		—		289,230		289,230		—
Long-term borrowings	5,136,732		4,947,647		(189,085)		4,434,323		4,354,037		(80,286)
Accrued interest payable	75,196		75,196		—		75,158		75,158		—
Derivative instruments	—		—		—		1,164		1,164		—
Total interest-bearing liabilities	$	28,621,763	$	28,132,281	$	(489,482)	$	29,228,573	$	29,002,495	$	(226,078)
Excess of net asset fair value over carrying value					$	2,991,929					$	2,039,809