Delinquency Aging Analysis by Loan Class (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012		Dec. 31, 2011
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	$ 10,068		$ 9,786
30-59 days past due	39		24
60-89 days past due	6		4
Greater than 90 days	46		52
Total past due	91		80
Total loans to banking clients	10,159	[1]	9,866	[1]
Residential real estate mortgages, originated and purchased first mortgages
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	5,751
30-59 days past due	30
60-89 days past due	3
Greater than 90 days	33
Total past due	66
Total loans to banking clients	5,817
Residential real estate mortgages, other purchased first mortgages
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	160
30-59 days past due	1
Greater than 90 days	4
Total past due	5
Total loans to banking clients	165
Residential real estate mortgages, originated first mortgages
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			5,380
30-59 days past due			16
60-89 days past due			2
Greater than 90 days			39
Total past due			57
Total loans to banking clients			5,437
Residential real estate mortgages, purchased first mortgages
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current			152
30-59 days past due			2
Greater than 90 days			5
Total past due			7
Total loans to banking clients			159
Home equity lines of credit
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	3,326		3,494
30-59 days past due	8		5
60-89 days past due	3		2
Greater than 90 days	9		8
Total past due	20		15
Total loans to banking clients	3,346		3,509
Personal loans secured by securities
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	807		741
30-59 days past due			1
Total past due			1
Total loans to banking clients	807		742
Other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	24		19
Total loans to banking clients	$ 24		$ 19

[1] All loans are evaluated for impairment by loan segment.