Long-Term Debt Debt Maturity Schedule (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Long-term debt	$ 384,949,000us-gaap_LongTermDebt	$ 335,551,000us-gaap_LongTermDebt
Mortgages [Member]
Debt Instrument [Line Items]
Loan amortization period	25 years
Number of monthly principal and interest payments	120
Fiscal Year Amortization Schedule [Abstract]
Total payment, 2015	1,229,000
Total payment, 2016	4,034,000
Total payment, 2017	11,470,000
Interest, 2015	856,000
Interest, 2016	762,000
Interest, 2017	110,000
Principal, 2015	373,000
Principal, 2016	3,272,000
Principal, 2017	11,360,000
Mortgages [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Stated interest rates	5.61%
Mortgages [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Stated interest rates	6.09%
Mortgages [Member] \| 444 West Santa Clara Street, L.P. [Member]
Debt Instrument [Line Items]
Loan amortization period	20 years
Long-term debt	2,947,000	3,053,000
Stated interest rates	5.68%
Fiscal Year Amortization Schedule [Abstract]
Total payment, 2015	276,000
Total payment, 2016	276,000
Total payment, 2017	276,000
Total payment, 2018	276,000
Total payment, 2019	276,000
Total payment, thereafter	2,485,000
Interest, 2015	164,000
Interest, 2016	157,000
Interest, 2017	150,000
Interest, 2018	143,000
Interest, 2019	135,000
Interest, thereafter	169,000
Principal, 2015	112,000
Principal, 2016	119,000
Principal, 2017	126,000
Principal, 2018	133,000
Principal, 2019	141,000
Principal, thereafter	2,316,000
444 West Santa Clara Street, L.P. [Member]
Debt Instrument [Line Items]
Limited partership interest percentage	70.00%
San Jose Water Company [Member] \| Standby Letters of Credit [Member]
Debt Instrument [Line Items]
Standby letters of credit	3,000,000
Fiscal Year Amortization Schedule [Abstract]
Line of Credit Facility, Renewal Term	1 year
San Jose Water Company [Member] \| Bonds [Member] \| California Pollution Control Financing Authority Revenue Bonds [Member]
Debt Instrument [Line Items]
Long-term debt	50,000,000	50,000,000
Stated interest rates	5.10%
San Jose Water Company [Member] \| SDWSRF loans [Member]
Debt Instrument [Line Items]
Long-term debt	1,997,000	2,141,000
Fiscal Year Amortization Schedule [Abstract]
Total payment, 2015	132,000
Total payment, 2016	195,000
Total payment, 2017	196,000
Total payment, 2018	196,000
Total payment, 2019	196,000
Total payment, thereafter	1,397,000
Interest, 2015	34,000
Interest, 2016	45,000
Interest, 2017	42,000
Interest, 2018	38,000
Interest, 2019	34,000
Interest, thereafter	122,000
Principal, 2015	98,000
Principal, 2016	150,000
Principal, 2017	154,000
Principal, 2018	158,000
Principal, 2019	162,000
Principal, thereafter	$ 1,275,000
San Jose Water Company [Member] \| SDWSRF loans [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Stated interest rates	2.39%
San Jose Water Company [Member] \| SDWSRF loans [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Stated interest rates	2.60%	2.60%

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Long-term Debt, Maturities, Repayments of Interest after Year Five

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Contractual interest rate for funds borrowed, under the debt agreement.

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The number of units or percentage investment held by one or more members or limited partners of the LLC or LP.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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