Commitments and Contingencies (Lease Disclosures) (Detail) $ in Millions	Jun. 30, 2021 USD ($)
Operating lease liability	us-gaap:OperatingLeaseLiability
Operating lease weighted average remaining lease term	8 years 6 months
Operating lease weighted average discount rate percent	7.50%
Operating leases future minimum payments due	$ 27
Other Assets [Member]
Operating lease right of use asset	19
Other Liabilities [Member]
Operating lease liability	$ 19