Investments in Marketable Securities (Tables)

9 Months Ended

Dec. 31, 2021

Marketable Securities [Abstract]

Summary of Investments in Marketable Securities

Investments in marketable securities consisted of the following:

	December 31, 2021
	Amortized		Unrealized		Unrealized			Fair
	cost		gains		losses			value
Available-for-sale debt securities:
U.S. government and agency obligations	$	491	$	5	$	(6	)	$	490
Foreign government and agency obligations		32		-		(1	)		31
Municipal debt securities		9		2		-			11
Commercial paper		25		-		-			25
Corporate debt securities		589		15		(3	)		601
Mortgage-backed securities:
U.S. government agency		21		1		-			22
Non-agency residential		11		-		-			11
Non-agency commercial		75		2		(1	)		76
Asset-backed securities		86		3		(1	)		88
Total available-for-sale debt securities	$	1,339	$	28	$	(12	)	$	1,355
Equity investments									3,766
Total investments in marketable securities								$	5,121

	March 31, 2021
	Amortized		Unrealized		Unrealized			Fair
	cost		gains		losses			value
Available-for-sale debt securities:
U.S. government and agency obligations	$	217	$	4	$	(10	)	$	211
Municipal debt securities		8		2		-			10
Commercial paper		196		-		-			196
Corporate debt securities		177		12		(2	)		187
Mortgage-backed securities:
U.S. government agency		31		1		-			32
Non-agency residential		1		-		-			1
Non-agency commercial		47		2		(2	)		47
Asset-backed securities		49		3		-			52
Total available-for-sale debt securities	$	726	$	24	$	(14	)	$	736
Equity investments									4,084
Total investments in marketable securities								$	4,820

Schedule of Gains and Losses on Investments in Marketable Securities Presented in Our Consolidated Statement of Income

The following table represents gains and losses on our investments in marketable securities presented in our Consolidated Statements of Income:

	Three months ended					Nine months ended
	December 31,					December 31,
	2021			2020		2021			2020
Available-for-sale debt securities:
Unrealized (losses) gains on securities for which the fair value option was elected	$	(4	)	$	-	$	3		$	-
Realized (losses) gains	$	(1	)	$	2	$	(1	)	$	19
Equity investments:
Unrealized gains	$	26		$	49	$	84		$	188
Realized gains on sales	$	-		$	3	$	22		$	15

Summary of Contractual Maturities of Available-For-Sale Debt Securities

The amortized cost and fair value by contractual maturities of available-for-sale debt securities are summarized in the following table.  Actual maturities may differ from contractual maturities because certain borrowers have the right to call or prepay certain obligations.

	December 31, 2021
	Amortized cost		Fair value
Available-for-sale debt securities:
Due within 1 year	$	127	$	127
Due after 1 year through 5 years		372		375
Due after 5 years through 10 years		357		359
Due after 10 years		290		297
Mortgage-backed and asset-backed securities 1		193		197
Total	$	1,339	$	1,355

^{1 Mortgage-backed and asset-backed securities are shown separately from other maturity groupings as these securities have multiple maturity dates.}