Investment Securities (Tables)

3 Months Ended

Mar. 31, 2017

Investments, Debt and Equity Securities [Abstract]

Investments

	March 31, 2017								December 31, 2016
			Gross		Gross						Gross		Gross
	Amortized		unrealized		unrealized		Estimated		Amortized		unrealized		unrealized		Estimated
(In millions)	cost		gains		losses		fair value (a)		cost		gains		losses		fair value (a)
Debt
U.S. corporate		20,197		3,165		(84)		23,279		20,049		3,081		(85)		23,046
Non-U.S. corporate		9,468		89		(22)		9,535		11,917		98		(27)		11,987
State and municipal		3,921		432		(80)		4,274		3,916		412		(92)		4,236
Mortgage and asset-backed		2,723		102		(28)		2,797		2,787		111		(37)		2,861
Government and agencies		1,744		86		(27)		1,803		1,842		160		(26)		1,976
Equity		167		95		(1)		262		154		55		(1)		208
Total		38,220		3,971		(242)		41,949		40,665		3,917		(269)		44,313

Schedule of investments, by type and length in continuous loss position

ESTIMATED FAIR VALUE AND GROSS UNREALIZED LOSSES OF AVAILABLE-FOR-SALE INVESTMENT SECURITIES
	In loss position for
	Less than 12 months				12 months or more
			Gross				Gross
	Estimated		unrealized		Estimated		unrealized
(In millions)	fair value		losses		fair value		losses
March 31, 2017
Debt
U.S. corporate	$	1,586	$	(57)	$	337	$	(26)
Non-U.S. corporate		5,020		(21)		14		(1)
State and municipal		480		(21)		161		(59)
Mortgage and asset-backed		830		(20)		92		(8)
Government and agencies		553		(27)		-		-
Equity		3		(1)		-		-
Total	$	8,472	$	(148)	$	605	$	(95)
December 31, 2016
Debt
U.S. corporate	$	1,692	$	(55)	$	359	$	(30)
Non-U.S. corporate		5,352		(26)		14		(1)
State and municipal		674		(27)		158		(64)
Mortgage and asset-backed		822		(21)		132		(16)
Government and agencies		549		(26)		-		-
Equity		9		(1)		-		-
Total	$	9,098	$	(157)	$	663	$	(111)

Schedule of contractual maturities

CONTRACTUAL MATURITIES OF INVESTMENT IN AVAILABLE-FOR-SALE DEBT SECURITIES
(EXCLUDING MORTGAGE AND ASSET-BACKED SECURITIES)
	Amortized		Estimated
(In millions)	cost		fair value
Due
Within one year	$	7,446	$	7,446
After one year through five years		5,029		5,215
After five years through ten years		5,134		5,556
After ten years		17,721		20,673