Income Taxes (Narrative) (Detail) - USD ($) $ in Millions		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Non Variable Interest Entities [Line Items]
Federal statutory rate		35.00%	35.00%	35.00%
Valuation Allowance Deferred Tax Asset Change In Amount		$ 472
NOL carryforward		2,800
Alternative minimum tax credit carryforward - Other assets		30
Foreign tax credit		62	$ 7
Unrecognized Tax Benefits		0	0
Valuation allowance on net deferred tax asset		$ 770	7
SubsequentEvent [Member]
Non Variable Interest Entities [Line Items]
New federal corporate tax rate	21.00%
Other Liabilities [Member]
Non Variable Interest Entities [Line Items]
Non U.S. deferred tax liability			$ 36