Related Party Transactions (Brightstar) (Details) - Brightstar [Member] - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Mar. 31, 2015
Related Party Transaction [Line Items]
Accounts receivable	$ 156		$ 430
Accounts payable	114		$ 96
Revenue from Related Parties	375	$ 17
Related Party Costs	$ 418	$ 16