The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

Commitments (Visa Funding and Bancorp Cash Payments) (Detail) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Jul. 31, 2018	Sep. 30, 2014	Sep. 30, 2012	Mar. 31, 2012	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010	Jun. 30, 2018	Dec. 31, 2009
Visa Funding
Loss Contingencies
Escrow Deposit		$ 450	$ 150	$ 1,565	$ 400	$ 800	$ 500	$ 600	$ 3,000
Bancorp Cash Payment
Loss Contingencies
Reduction of liability in cash to the swap counterparty	$ 26	$ 18	$ 6	$ 75	$ 19	$ 35	$ 20