Securities - Summary of Securities Available-for-Sale Investments (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Fair Value	$ 80		$ 188
Securities available-for-sale - continuing operations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	80		188
Gross Unrealized Gains	0		1
Gross Unrealized Losses	0		(1)
Fair Value	80		188
Securities available-for-sale - discontinued operations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,231	[1]	1,694	[1]
Gross Unrealized Gains	180	[1]	165	[1]
Gross Unrealized Losses	0	[1]	(8)	[1]
Fair Value	1,411	[1]	1,851	[1]
U.S. Treasury [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost			80
Gross Unrealized Gains			0
Gross Unrealized Losses			0
Fair Value			80
U.S. government sponsored enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost			1	[2]
Gross Unrealized Gains			0	[3]
Gross Unrealized Losses			0	[3]
Fair Value			1	[2]
U.S. corporate debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost			57	[3]
Gross Unrealized Gains			1	[3]
Gross Unrealized Losses			(1)	[3]
Fair Value			57	[3]
Foreign debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost			26	[4]
Gross Unrealized Gains			0	[3]
Gross Unrealized Losses			0	[3]
Fair Value			26	[4]
Equity securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost			10
Gross Unrealized Gains			0
Gross Unrealized Losses			0
Fair Value			10
Money market funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	80		13
Gross Unrealized Gains	0		0
Gross Unrealized Losses	0		0
Fair Value	80		13
Subtotal [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost			187
Gross Unrealized Gains			1
Gross Unrealized Losses			(1)
Fair Value			187
Accrued investment income [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost			1
Gross Unrealized Gains			0
Gross Unrealized Losses			0
Fair Value			$ 1

[1] Securities available-for-sale in our discontinued operations relates to our discontinued Insurance business and primarily consists of U.S. corporate debt securities, money market funds and foreign debt securities at December 31, 2012 and 2011.

[2] Represents mortgage-backed securities issued by the Federal National Mortgage Association and the Federal Home Loan Mortgage Corporation as of December 31, 2011.

[3] The majority of our U.S. corporate debt securities represented investments in the financial services, consumer products and insurance sectors at December 31, 2011.

[4] We did not hold any foreign debt securities issued by the governments of Portugal, Ireland, Italy, Greece or Spain at December 31, 2011. We did not hold any foreign debt securities at December 31, 2012.