Loans, Lending Commitments and Allowance for Credit Losses (TDR) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Troubled Debt Restructurings
Loans	$ 38	$ 51
Lending commitments	45	28
Allowance for loan losses and lending commitments	$ 4	$ 10

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

Name:	us-gaap_FinancingReceivableModificationsRecordedInvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant