Line of Credit and Long-term Debt - Outstanding Indebtedness and Respective Principal Maturities (Details)	12 Months Ended
Dec. 31, 2020 USD ($)
Maturities of Long-term Debt [Abstract]
2021	$ 4,295,000
2022	4,475,000
2023	4,694,000
2024	4,901,000
2025	5,114,000
Thereafter	33,599,000
Total	$ 57,078,000
Selected LIBOR rate
Debt Instrument [Line Items]
Basis spread on variable rate	1.50%
Term Loan
Debt Instrument [Line Items]
Stated Rate	1.70%
Effective Rate	4.16%
Maturities of Long-term Debt [Abstract]
2021	$ 4,051,000
2022	4,221,000
2023	4,429,000
2024	4,624,000
2025	4,825,000
Thereafter	32,737,000
Total	54,887,000
RLOC
Debt Instrument [Line Items]
Face amount	35,000,000
Maturities of Long-term Debt [Abstract]
2021	0
2022	0
2023	0
2024	0
2025	0
Thereafter	0
Total	$ 0
Promissory note
Debt Instrument [Line Items]
Stated Rate	4.25%
Effective Rate	4.25%
Maturities of Long-term Debt [Abstract]
2021	$ 244,000
2022	254,000
2023	265,000
2024	277,000
2025	289,000
Thereafter	862,000
Total	$ 2,191,000

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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, after unamortized (discount) premium and debt issuance costs, of long-term debt. 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 requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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