Accumulated Other Comprehensive Income - Reclassifications Out of Accumulated Other Comprehensive Income (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2013
Accumulated Comprehensive Income Loss [Line Items]
Amount Reclassified from Accumulated Other Comprehensive Income	$ (7)	$ (21)
Total Before Income Taxes [Member]
Accumulated Comprehensive Income Loss [Line Items]
Amount Reclassified from Accumulated Other Comprehensive Income	12	28
Affected Line Item in the Statement Where Net Income is Presented	Income (loss) from continuing operations before income taxes	Income (loss) from continuing operations before income taxes
Income Taxes [Member]
Accumulated Comprehensive Income Loss [Line Items]
Amount Reclassified from Accumulated Other Comprehensive Income		11
Affected Line Item in the Statement Where Net Income is Presented		Income taxes
Net of Income Taxes [Member]
Accumulated Comprehensive Income Loss [Line Items]
Amount Reclassified from Accumulated Other Comprehensive Income		17
Affected Line Item in the Statement Where Net Income is Presented		Income (loss) from continuing operations
Interest Rate [Member] | Interest Income [Member]
Accumulated Comprehensive Income Loss [Line Items]
Amount Reclassified from Accumulated Other Comprehensive Income	13	35
Affected Line Item in the Statement Where Net Income is Presented	Interest income - Loans	Interest income - Loans
Interest Rate [Member] | Interest Expense [Member]
Accumulated Comprehensive Income Loss [Line Items]
Amount Reclassified from Accumulated Other Comprehensive Income	(1)	(4)
Affected Line Item in the Statement Where Net Income is Presented	Interest expense - Long term debt	Interest expense - Long term debt
Foreign Exchange [Member] | Other Income [Member]
Accumulated Comprehensive Income Loss [Line Items]
Amount Reclassified from Accumulated Other Comprehensive Income		(3)
Affected Line Item in the Statement Where Net Income is Presented	Other income	Other income
Foreign Currency Translation Adjustments [Member] | Total Before Income Taxes [Member]
Accumulated Comprehensive Income Loss [Line Items]
Amount Reclassified from Accumulated Other Comprehensive Income		7
Affected Line Item in the Statement Where Net Income is Presented		Income (loss) from continuing operations before income taxes
Foreign Currency Translation Adjustments [Member] | Income Taxes [Member]
Accumulated Comprehensive Income Loss [Line Items]
Amount Reclassified from Accumulated Other Comprehensive Income	5	3
Affected Line Item in the Statement Where Net Income is Presented	Income taxes	Income taxes
Foreign Currency Translation Adjustments [Member] | Net of Income Taxes [Member]
Accumulated Comprehensive Income Loss [Line Items]
Amount Reclassified from Accumulated Other Comprehensive Income	7	4
Affected Line Item in the Statement Where Net Income is Presented	Income (loss) from continuing operations	Income (loss) from continuing operations
Foreign Currency Translation Adjustments [Member] | Corporate Services Income [Member]
Accumulated Comprehensive Income Loss [Line Items]
Amount Reclassified from Accumulated Other Comprehensive Income		$ 7
Affected Line Item in the Statement Where Net Income is Presented		Corporate services income