Other Financial Data - Schedule of Other Current Assets (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Other Financial Data [Abstract]
Taxes receivable	$ 244	$ 99
Deferred tax assets	208	212
Prepaid expenses	161	164
Deferred project costs	101	102
Other	14	25
Total	$ 728	$ 602