Long-Term Debt and Credit Facilities - Additional Information (Details) $ in Millions	3 Months Ended
Sep. 30, 2018 USD ($)
Long-term Debt and Credit Facilities
Repayments of debt	$ 1,300
Senior notes \| Qwest Notes Due 2051
Long-term Debt and Credit Facilities
Repayments of debt	$ 164
Stated interest rate	7.50%
Senior notes \| Qwest Notes due 2052
Long-term Debt and Credit Facilities
Repayments of debt	$ 925
Stated interest rate	7.00%
Senior notes \| Qwest Notes 2035
Long-term Debt and Credit Facilities
Repayments of debt	$ 250
Stated interest rate	7.25%

Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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.

+ References

No definition available.

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

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