Fair Value (Tables)

12 Months Ended

Dec. 31, 2022

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Financial Assets and Liabilities, Measured at Fair Value Recurring Basis [Table Text Block]

The following table presents a summary of fair value measurements by level and carrying values for items measured at fair value on a recurring basis in the Consolidated Balance Sheets:

(in millions)	Quoted Prices in Active Markets (Level 1)			Other Observable Inputs (Level 2)			Unobservable Inputs (Level 3)			Total Fair and Carrying Value
December 31, 2022
Cash and cash equivalents	$	23,202		$	163		$	—		$	23,365
Debt securities - available-for-sale:
U.S. government and agency obligations	3,505			304			—			3,809
State and municipal obligations	—			7,248			—			7,248
Corporate obligations	7			21,695			192			21,894
U.S. agency mortgage-backed securities	—			6,586			—			6,586
Non-U.S. agency mortgage-backed securities	—			2,784			—			2,784
Total debt securities - available-for-sale	3,512			38,617			192			42,321
Equity securities	2,043			35			70			2,148
Assets under management	1,788			2,203			96			4,087
Total assets at fair value	$	30,545		$	41,018		$	358		$	71,921
Percentage of total assets at fair value	42		%	57		%	1		%	100		%
December 31, 2021
Cash and cash equivalents	$	21,359		$	16		$	—		$	21,375
Debt securities - available-for-sale:
U.S. government and agency obligations	3,017			181			—			3,198
State and municipal obligations	—			7,106			—			7,106
Corporate obligations	40			20,916			218			21,174
U.S. agency mortgage-backed securities	—			5,901			—			5,901
Non-U.S. agency mortgage-backed securities	—			2,838			—			2,838
Total debt securities - available-for-sale	3,057			36,942			218			40,217
Equity securities	2,090			23			64			2,177
Assets under management	1,972			2,376			101			4,449
Total assets at fair value	$	28,478		$	39,357		$	383		$	68,218
Percentage of total assets at fair value	42		%	57		%	1		%	100		%

Fair Value Measurements, Nonrecurring [Table Text Block]

The following table presents a summary of fair value measurements by level and carrying values for certain financial instruments not measured at fair value on a recurring basis in the Consolidated Balance Sheets:

(in millions)	Quoted Prices in Active Markets (Level 1)		Other Observable Inputs (Level 2)		Unobservable Inputs (Level 3)		Total Fair Value		Total Carrying Value
December 31, 2022
Debt securities - held-to-maturity	$	577	$	102	$	—	$	679	$	696
Long-term debt and other financing obligations	$	—	$	53,626	$	—	$	53,626	$	56,823
December 31, 2021
Debt securities - held-to-maturity	$	534	$	102	$	7	$	643	$	641
Long-term debt and other financing obligations	$	—	$	52,583	$	—	$	52,583	$	46,003