Labor Union Contracts	6 Months Ended
Jun. 30, 2020
Risks and Uncertainties [Abstract]
Labor Union Contracts	Labor Union ContractsAs of June 30, 2020, approximately, 24% of our employees were represented by the Communication Workers of America ("CWA") or the International Brotherhood of Electrical Workers ("IBEW"). Approximately 1% of our union-represented employees were subject to collective bargaining agreements that expired as of June 30, 2020 and are currently being renegotiated. Approximately 13% of our represented employees are subject to collective bargaining agreements that are scheduled to expire over the next 12 months.

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

Name:	us-gaap_ConcentrationRiskDisclosureTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration