Other Income, Net - Additional Information (Details) $ in Millions	3 Months Ended			12 Months Ended
	Sep. 30, 2014 USD ($) VEF / $	Mar. 31, 2014 USD ($) VEF / $	Mar. 31, 2013 USD ($)	Dec. 31, 2014 USD ($) VEF / $	Dec. 31, 2013 USD ($)	Feb. 28, 2013 VEF / $	Jan. 31, 2013 VEF / $
Interest income, gross receipts tax					$ 3
Amount charged to expense due to inflationary accounting	$ 3	$ 17	$ 6
Official Exchange [Member]
Foreign Currency Exchange Rate, Remeasurement | VEF / $						6.3	4.3
Foreign currency transaction gain (loss), realized				$ 8
SICAD [Member]
Foreign Currency Exchange Rate, Remeasurement | VEF / $	12.0	10.7
SICAD2 [Member]
Foreign currency transaction gain (loss), realized				$ 14
Average transacted exchange rate | VEF / $				49.9
Other Income, Net Error [Member]
Quantifying Misstatement in Current Year Financial Statements, Amount	$ 6