Financial Instruments with Off-Balance-Sheet Risk (Narrative) (Details) $ in Millions	Mar. 31, 2019 USD ($)
Financial Instruments With Off Balance Sheet Risk [Abstract]
Letters of Credit Outstanding, Amount	$ 95

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant