Subsequent Events (Details) $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($)
Minimum
Subsequent Event
October 2020 Delta & Zeta loss estimate	$ 50
Maximum
Subsequent Event
October 2020 Delta & Zeta loss estimate	$ 55

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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