Commitments and Contingencies Commitment and Contingencies (Details)	Sep. 30, 2017
Subject to Capital Lease with Sprint, TMO, or AT&T [Member]
Other Commitments [Line Items]
Purchase Option, Percentage of Towers	53.00%

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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