Income Taxes (Narrative) (Details) $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($)
AMT credit carryforwards
Tax Credit Carryforward [Line Items]
Tax refund	$ 572

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_TaxCreditCarryforwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration