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Leases Lease -additional information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jan. 01, 2019	Dec. 31, 2018
Leases [Abstract]
Operating lease right-of-use assets	$ 13,017		$ 13,017		$ 7,600	$ 0
Operating lease liabilities	1,841		1,841			0
Operating lease liabilities	11,536		11,536			0
Short-term Lease Payments			806
Debt Instrument [Line Items]
Operating Lease, Expense	683	$ 569	2,000	$ 1,700
Notes Payable 9.56 Percent Due 2031 [Member]
Debt Instrument [Line Items]
Notes Payable to Bank	$ 28,000		$ 28,000
Debt Instrument, Interest Rate, Stated Percentage	9.56%		9.56%
Golden State Water Company [Member]
Leases [Abstract]
Operating lease right-of-use assets	$ 12,494		$ 12,494			0
Operating lease liabilities	1,559		1,559			0
Operating lease liabilities	$ 11,331		$ 11,331			$ 0
Debt Instrument [Line Items]
Ratio of Indebtedness to Net Capital	0.4377		0.4377
Golden State Water Company [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Ratio of Indebtedness to Net Capital	0.6667		0.6667