Commitments and Contingencies (Details) $ in Millions	Sep. 30, 2017 USD ($)
Satellite-related obligations
Other Commitments [Line Items]
Satellite-related obligations	$ 1,010

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Balance Type:	na
Period Type:	duration