Subsequent Events Subsequent events (Details) - Subsequent Event [Member] - USD ($) $ in Millions	1 Months Ended	2 Months Ended	3 Months Ended	57 Months Ended
Apr. 29, 2016	Jun. 30, 2016	Jun. 30, 2016	Dec. 31, 2020
Subsequent Event [Line Items]
Restriction On Common Dividends				67.00%
Assets Purchased From Related Parties	$ 729	$ 10
Percentage Of Shareholding Acquired			36.00%

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