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Dispositions (Details) $ in Thousands	1 Months Ended		12 Months Ended
Dispositions (Details) $ in Thousands	Oct. 31, 2020 USD ($)	Apr. 30, 2019 USD ($)	Dec. 31, 2018 customer	Dec. 31, 2020
Virginia [Member] \| Disposal Group, Not Discontinued Operations [Member]
Discontinued Operations And Other Dispositions [Line Items]
Number of customers \| customer			500
Total proceeds		$ 1,882
Net gain (loss)		$ 405
Joint Venture [Member]
Discontinued Operations And Other Dispositions [Line Items]
Joint venture ownership percentage				49.00%
Joint Venture [Member] \| Disposal Group, Not Discontinued Operations [Member]
Discontinued Operations And Other Dispositions [Line Items]
Joint venture ownership percentage	49.00%
Gain (loss) on sale	$ 3,700