Long-Term Debt and Short-Term Borrowings (Details) - USD ($)	Jul. 01, 2021	Dec. 31, 2020
Long-Term Debt and Short-Term Borrowings
Mortgage notes	$ 24,482,000	$ 24,482,000
Senior notes	100,000,000	100,000,000
Unsecured term note due February 2025, with monthly principal and interest payments of $39,110, bearing interest at 5.75%	1,548,000	1,735,000
Convertible senior notes	100,050,000	100,050,000
Payroll Protection Program loans	3,424,000	3,424,000
Revolving credit agreement	20,000,000
Term loan facility	50,000,000
Debt issuance costs	(4,440,000)	(3,684,000)
Long-term Debt, Total	295,064,000	226,007,000
Less current maturities, net of issuance costs	11,171,000	10,548,000
Less debt discount		22,423,000
Long-term Debt, Excluding Current Maturities, Total	$ 283,893,000	$ 193,036,000

Amount of long-term debt discount.

No definition available.

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- Definition

Carrying amount of loans granted under Payroll Protection Program under the CARES Act, with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion.

+ References

No definition available.

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- Definition

The amount of long term debt under term loan facility.

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of unsecured notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

+ References

No definition available.

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- Definition

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

+ References

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- References

No definition available.

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- Definition

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

+ References

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- Definition

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.

+ References

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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- Definition

The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

+ References

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- Definition

Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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