Amount for accounts payable to related parties.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 210
-SubTopic 10
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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

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Related Party Transactions (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019
Related Party Transaction [Line Items]
Accounts Payable, Related Parties					$ 154
Brightstar [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	$ 14	$ 18	$ 41	$ 51
Related Party Transaction, Other Revenues from Transactions with Related Party	50	$ 52	134	$ 149
Brightstar [Member] \| Line of Credit [Member]
Related Party Transaction [Line Items]
Aggregate principal amount line of credit	$ 700		$ 700