Income Taxes (Narrative) (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Non Variable Interest Entities [Line Items]
Net deferred tax asset	$ 917,000,000
Capital losses carryforward period in years	5 years
NOL carryforward	3,100,000,000	2,800,000,000
Minimum tax credit carryforward		22,000,000
Non Variable Interest Entities [Member]
Non Variable Interest Entities [Line Items]
Valuation allowance	95,000,000	93,000,000
Valuation Allowance Deferred Tax Asset Change In Amount	$ 2,000,000