Investments in Marketable Securities (Tables)

3 Months Ended

Dec. 31, 2014

Investments in Marketable Securities [Abstract]

Summary of Investments in Marketable Securities

				December 31, 2014
				Amortized		Unrealized		Unrealized		Fair
(Dollars in millions)				cost		gains		losses		value
Available-for-sale securities:
	Debt instruments:
		U.S. government and agency obligations		$	2,010	$	1	$	(1)	$	2,010
		Municipal debt securities			10		2		-		12
		Corporate debt securities			179		6		(1)		184
		Mortgage-backed securities:
			U.S. government agency		53		2		-		55
			Non-agency residential		3		1		-		4
			Non-agency commercial		45		1		(1)		45
		Asset-backed securities			25		-		-		25
	Equity instruments:
		Fixed income mutual funds:
			Short-term floating NAV fund II		190		-		-		190
			Short-term sector fund		35		2		-		37
			U.S. government sector fund		275		14		-		289
			Municipal sector fund		18		1		-		19
			Investment grade corporate sector fund		255		14		(4)		265
			High-yield sector fund		32		5		(1)		36
			Real return sector fund		235		-		(8)		227
			Mortgage sector fund		441		7		-		448
			Asset-backed securities sector fund		35		8		-		43
			Emerging market sector fund		57		-		(2)		55
			International sector fund		142		9		-		151
		Equity mutual fund			196		280		-		476
Total investments in marketable securities				$	4,236	$	353	$	(18)	$	4,571

Note 3 – Investments in Marketable Securities (Continued)
					March 31, 2014
				Amortized		Unrealized		Unrealized		Fair
(Dollars in millions)				cost		gains		losses		value
Available-for-sale securities:
	Debt instruments:
		U.S. government and agency obligations		$	652	$	1	$	(1)	$	652
		Municipal debt securities			10		1		-		11
		Certificates of deposit			1,599		-		-		1,599
		Commercial paper			507		-		-		507
		Corporate debt securities			164		6		(1)		169
		Mortgage-backed securities:
			U.S. government agency		60		1		(1)		60
			Non-agency residential		4		1		-		5
			Non-agency commercial		44		1		(2)		43
		Asset-backed securities			27		-		-		27
	Equity instruments:
		Fixed income mutual funds:
			Short-term sector fund		41		3		-		44
			U.S. government sector fund		329		-		(2)		327
			Municipal sector fund		21		1		-		22
			Investment grade corporate sector fund		283		33		-		316
			High-yield sector fund		38		7		-		45
			Real return sector fund		275		-		(1)		274
			Mortgage sector fund		519		1		-		520
			Asset-backed securities sector fund		40		10		-		50
			Emerging market sector fund		65		1		-		66
			International sector fund		170		2		(1)		171
		Equity mutual fund			217		264		-		481
Total investments in marketable securities				$	5,065	$	333	$	(9)	$	5,389

Schedule of realized gains and losses on sales from AFS

		Three Months Ended December 31,				Nine Months Ended December 31,
(Dollars in millions)		2014		2013		2014		2013
Available-for-sale securities:
	Realized gains on sales	$	11	$	12	$	55	$	28
	Realized losses on sales	$	-	$	-	$	-	$	(3)
	Other-than-temporary impairment	$	-	$	(1)	$	-	$	(54)

Summary of Contractual Maturities of Available-for-Sale Securities

		December 31, 2014
(Dollars in millions)		Amortized Cost		Fair Value
Available-for-sale debt instruments:
	Due within 1 year	$	1,929	$	1,927
	Due after 1 year through 5 years		135		136
	Due after 5 years through 10 years		81		83
	Due after 10 years		54		60
	Mortgage-backed and asset-backed securities1		126		129
Total		$	2,325	$	2,335
1Mortgage-backed and asset-backed securities are shown separately because these securities do not have a single maturity date.