Long-Term Debt (Narrative) (Detail) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Long Term Debt Other Disclosures [Abstract]
Weighted average interest rate	8.50%	8.50%
Market value	$ 14,900	$ 15,200
Receivables Based Facility Due 2017 [Member]
Long Term Debt Other Disclosures [Abstract]
Line of credit facility maximum borrowing capacity	535
Subsidiary Senior Revolving Credit Facility Due 2018 [Member]
Long Term Debt Other Disclosures [Abstract]
Line of credit facility maximum borrowing capacity	$ 75