Business Events (Details Textuals) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Business Events (Line Items)
Gain on sale of held for sale (HFS) portfolio	$ 0	$ (127)
Other Expense [Member]
Business Events (Line Items)
Gain on sale of held for sale (HFS) portfolio	$ 0	$ (127)

The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3337-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3461-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 230
-Section 55
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=34726456&loc=d3e60097-112785

Name:	us-gaap_ProceedsFromSaleOfLoansHeldForSale
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration