CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 4,425	$ 2,550
Cash flows from operating activities
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	173	206
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	2,330	2,054
Bad debt expense	57	102
Share-based and long-term incentive compensation expense	40	41
Deferred income tax benefit	39	282
Gains from asset dispositions and exchanges	0	479
Call premiums paid on debt redemptions	0	(129)
Loss on early extinguishment of debt	0	66
Amortization and accretion of long-term debt premiums and discounts	(33)	(51)
Loss on Disposition of Property Plant Equipment	124	293
Other changes in assets and liabilities:
Accounts and notes receivable	273	(53)
Deferred purchase price from sale of receivables	(170)	(375)
Inventories and other current assets	421	181
Accounts payable and other current liabilities	(766)	(474)
Non-current assets and liabilities, net	(197)	73
Other, net	139	58
Net cash provided by operating activities	2,430	1,924
Cash flows from investing activities
Capital expenditures - network and other	(1,132)	(1,151)
Capital expenditures - leased devices	(1,817)	(1,359)
Expenditures relating to FCC licenses	(59)	(13)
Proceeds from sales and maturities of short-term investments	810	2,594
Purchases of short-term investments	(2,464)	(1,499)
Proceeds from sales of assets and FCC Licenses	133	101
Other, net	(10)	(1)
Net Cash Used in Investing Activities	(4,369)	(953)
Cash flows from financing activities
Proceeds from debt and financings	1,370	902
Repayments of debt and capital lease obligations	(1,415)	(2,121)
Debt financing costs	248	0
Other, net	(2)	(15)
Net cash provided by (used in) financing activities	(295)	(1,363)
Net decrease in cash and cash equivalents		(392)
Cash, Cash Equivalents, Restricted Cash, Restricted Cash Equivalents, Period Increase (Decrease)	(2,234)	(392)
Cash and cash equivalents, beginning of period	6,610	2,942
Cash and cash equivalents, end of period	4,378	2,550
Proceeds from Sale and Collection of Receivables	$ 170	375
Accounting Standards Update 2016-15 [Member]
Cash flows from investing activities
Net Cash Used in Investing Activities		(2)
Cash flows from financing activities
Net cash provided by (used in) financing activities		$ 129