OTHER DEFERRED CREDITS AND OTHER LIABILITIES (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Deferred credits and other liabilities
Transmission easements	$ 20,687	$ 20,966
Operating lease liabilities - noncurrent	2,001
Contract liabilities (unearned revenue) - noncurrent	4,311	4,592
Customer deposits	2,367	2,458
Other	19,562	22,250
Total other deferred credits and other liabilities	48,928	50,266
Transmission Right of Way Easements
Deferred credits and other liabilities
Total due for easement right of way	31,800
Other Deferred Credits and Other Liabilities | Transmission Right of Way Easements
Deferred credits and other liabilities
Transmission easements	$ 20,700	$ 21,000