The amount of net gains (losses) from changes in fair value of interest rate cash flow hedges.

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Amount of the total principal payments made during the annual reporting period.

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Face (par) amount of debt instrument at time of issuance.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of the required periodic payments applied to interest.

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Amount of payment greater than the preceding installment payments to be paid at final maturity date of debt.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Nominal or face amount used to calculate payment on derivative.

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Fair value of the amount outstanding under the credit facility.

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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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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt (Narrative) (Details)			1 Months Ended		12 Months Ended
Debt (Narrative) (Details)	Aug. 04, 2021 USD ($)	May 18, 2017 USD ($) building	Mar. 31, 2020 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Aug. 05, 2021 USD ($)	Dec. 31, 2018 loan
Debt
Proceeds from borrowing under lines of credit							$ 1,238,000
Interest rate swaps
Debt
Gains (losses) from changes in fair values of interest rate swaps					$ 5,500,000	$ 1,500,000
Seine-Normandie Water Agency [Member]
Debt
Debt Instrument, Term				8 years
Number of Loans with Government Agency				500,000					2
Debt Instrument, Periodic Payment, Interest				$ 0
Notes Payable					200,000
Mortgage Payable - Due June 2027 \| East West Bank [Member]
Debt
Principal amount		$ 9,000,000.0
Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid		$ 7,400,000
Debt Instrument, Interest Rate, Stated Percentage		4.79%
Mortgage Payable - Due June 2027 \| East West Bank [Member] \| Rancho Cucamonga, California
Debt
Number of Buildings Securing Loan \| building		1
Mortgage Payable - Due June 2027 \| East West Bank [Member] \| Chino, California
Debt
Number of Buildings Securing Loan \| building		2
Mortgage Payable - Due June 2027 \| East West Bank [Member] \| LIBOR
Debt
Debt Instrument, Basis Spread on Variable Rate		2.50%
Credit Agreement - Expires March 2023 \| China Merchant Bank
Debt
Draw down period			36 months
Maximum borrowing capacity			$ 14,600,000
Line of Credit [Member] \| Capital One, N.A.
Debt
Maximum borrowing capacity	$ 140,000,000.0
Secured Debt [Member] \| Capital One, N.A.
Debt
Borrowings	70,000,000.0
Loan issuance costs					$ 2,100,000
Secured Debt [Member] \| Capital One, N.A. \| In the first two years
Debt
Debt Instrument, Annual Principal Payment	1,800,000
Secured Debt [Member] \| Capital One, N.A. \| Starting in the third year
Debt
Debt Instrument, Annual Principal Payment	3,500,000
Secured Debt [Member] \| Capital One, N.A. \| Starting in the fifth year
Debt
Debt Instrument, Annual Principal Payment	3,900,000
Secured Debt [Member] \| Capital One, N.A. \| Interest rate swaps
Debt
Notional Amount								$ 55,000,000.0
Interest rate swap, fair value								$ 0.93
Revolving Credit Facility \| Capital One, N.A.
Debt
Maximum borrowing capacity	$ 70,000,000.0
Minimum \| Secured Debt [Member] \| Capital One, N.A. \| LIBOR
Debt
Debt Instrument, Basis Spread on Variable Rate	0.50%
Maximum \| Secured Debt [Member] \| Capital One, N.A. \| LIBOR
Debt
Debt Instrument, Basis Spread on Variable Rate	2.50%