LEASES (Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Lease Assets
Utility Plant Under Finance Leases	$ 151,467	$ 248,635
Accumulated Amortization of Finance Lease Assets	(77,285)	$ (73,646)
Regulatory and Other Assets, Other	8,000
Lease Liabilities
Current Liabilities, Finance Lease Obligations	17,086
Total Non-Current Lease Obligations	67,316
Current Liabilities, Other	1,000
Regulatory and Other Liabilities, Other	$ 6,000