Labor Union Contracts	12 Months Ended
Dec. 31, 2019
Labor Union Contracts
Labor Union Contracts	Labor Union Contracts As of December 31, 2019, approximately 42% of our employees were members of various bargaining units represented by the Communication Workers of America ("CWA") and the International Brotherhood of Electrical Workers ("IBEW"). During the third quarter of 2019, we reached new agreements with the CWA and IBEW, which represented all of the above noted represented employees. Therefore, there are no collective bargaining agreements that are scheduled to expire over the next 12 months. We believe that relations with our employees continue to be generally good.

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

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