Subsequent Events	12 Months Ended
Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent Events	18. Subsequent Events On February 6, 2020, TEC entered into a 364-day, $300 million credit agreement with a group of banks. See Note 6 for additional information.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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