Investments in fixed maturity securities (Tables)

12 Months Ended

Dec. 31, 2021

Investments Debt And Equity Securities [Abstract]

Schedule of investments in securities with fixed maturities

Investments in fixed maturity securities as of December 31, 2021 and 2020 are summarized by type below (in millions).

	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
December 31, 2021
U.S. Treasury, U.S. government corporations and agencies	$	3,286	$	22	$	(5	)	$	3,303
Foreign governments		10,998		29		(33	)		10,994
Corporate bonds		1,363		412		(1	)		1,774
Other		317		47		(1	)		363
	$	15,964	$	510	$	(40	)	$	16,434
December 31, 2020
U.S. Treasury, U.S. government corporations and agencies	$	3,348	$	55	$	—		$	3,403
Foreign governments		11,233		110		(5	)		11,338
Corporate bonds		4,729		464		(2	)		5,191
Other		414		66		(2	)		478
	$	19,724	$	695	$	(9	)	$	20,410

Schedule of amortized cost and estimated fair value of securities with fixed maturities

	Due in one year or less		Due after one year through five years		Due after five years through ten years		Due after ten years		Mortgage-backed securities		Total
Amortized cost	$	9,171	$	6,044	$	307	$	207	$	235	$	15,964
Fair value		9,165		6,086		559		347		277		16,434