Fair Value Measurements - Carrying and Estimated Fair Value (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012
Financial assets:
Cash	$ 225		$ 197
Interest bearing deposits with banks	0		1,371
Securities purchased under agreements to resell	6,196		2,160
Securities	0		80
Financial liabilities:
Long-term debt	8,034		9,725
Long-term debt not carried at fair value	23,707		28,426
Derivative related liability	1		22
Level 1 [Member]
Financial assets:
Cash	225		197
Interest bearing deposits with banks	0		0
Securities purchased under agreements to resell	0		0
Securities			80
Real estate secured:
Total real estate secured	0	[1]	0	[1]
Receivables held for sale	0		0
Due from affiliates	0		0
Financial liabilities:
Due to affiliates carried at fair value	0		0
Due to affiliates not carried at fair value	0		0
Long-term debt	0		0
Long-term debt not carried at fair value	0		0
Derivative related liability	0		0
Level 1 [Member] | First Lien [Member]
Real estate secured:
Total real estate secured	0	[1]	0	[1]
Level 1 [Member] | Second Lien [Member]
Real estate secured:
Total real estate secured	0	[1]	0	[1]
Level 2 [Member]
Financial assets:
Cash	0		0
Interest bearing deposits with banks	0		1,371
Securities purchased under agreements to resell	6,196		2,160
Securities			0
Real estate secured:
Total real estate secured	0	[1]	0	[1]
Receivables held for sale	901		0
Due from affiliates	50		105
Financial liabilities:
Due to affiliates carried at fair value	493		514
Due to affiliates not carried at fair value	8,573		8,654
Long-term debt	8,034		9,725
Long-term debt not carried at fair value	13,800		16,537
Derivative related liability	1		22
Level 2 [Member] | First Lien [Member]
Real estate secured:
Total real estate secured	0	[1]	0	[1]
Level 2 [Member] | Second Lien [Member]
Real estate secured:
Total real estate secured	0	[1]	0	[1]
Level 3 [Member]
Financial assets:
Cash	0		0
Interest bearing deposits with banks	0		0
Securities purchased under agreements to resell	0		0
Securities			0
Real estate secured:
Total real estate secured	20,987	[1]	20,699	[1]
Receivables held for sale	3,816		6,203
Due from affiliates	0		0
Financial liabilities:
Due to affiliates carried at fair value	0		0
Due to affiliates not carried at fair value	0		0
Long-term debt	0		0
Long-term debt not carried at fair value	2,319		2,635
Derivative related liability	0		0
Level 3 [Member] | First Lien [Member]
Real estate secured:
Total real estate secured	19,496	[1]	19,586	[1]
Level 3 [Member] | Second Lien [Member]
Real estate secured:
Total real estate secured	1,491	[1]	1,113	[1]
Carrying Value [Member]
Financial assets:
Cash	225		197
Interest bearing deposits with banks	0		1,371
Securities purchased under agreements to resell	6,196		2,160
Securities			80
Real estate secured:
Total real estate secured	25,051	[1]	29,284	[1]
Receivables held for sale	4,717		6,203
Due from affiliates	50		105
Financial liabilities:
Due to affiliates carried at fair value	493		514
Due to affiliates not carried at fair value	8,472		8,575
Long-term debt	8,034		9,725
Long-term debt not carried at fair value	15,673		18,701
Derivative related liability	1		22
Carrying Value [Member] | First Lien [Member]
Real estate secured:
Total real estate secured	22,308	[1]	26,218	[1]
Carrying Value [Member] | Second Lien [Member]
Real estate secured:
Total real estate secured	2,743	[1]	3,066	[1]
Fair Value [Member]
Financial assets:
Cash	225		197
Interest bearing deposits with banks	0		1,371
Securities purchased under agreements to resell	6,196		2,160
Securities			80
Real estate secured:
Total real estate secured	20,987	[1]	20,699	[1]
Receivables held for sale	4,717		6,203
Due from affiliates	50		105
Financial liabilities:
Due to affiliates carried at fair value	493		514
Due to affiliates not carried at fair value	8,573		8,654
Long-term debt	8,034		9,725
Long-term debt not carried at fair value	16,119		19,172
Derivative related liability	1		22
Fair Value [Member] | First Lien [Member]
Real estate secured:
Total real estate secured	19,496	[1]	19,586	[1]
Fair Value [Member] | Second Lien [Member]
Real estate secured:
Total real estate secured	$ 1,491	[1]	$ 1,113	[1]

[1] The carrying amount of consumer receivables presented in the table above reflects the amortized cost of the receivable, including any accrued interest, less credit loss reserves as well as any charge-offs recorded in accordance with our existing charge-off policies.