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Long-term Debt and Related Matters - Narrative (Details) | Jun. 26, 2020 USD ($) | Mar. 31, 2021 USD ($) | Jan. 29, 2021 USD ($) | Dec. 31, 2020 USD ($) | Jun. 25, 2020 USD ($)
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Line of Credit Facility |  |  |  |  |
Line of credit facility, amount outstanding |  | $ 36,538,000 |  | $ 44,777,000 |
Second Amendment |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Minimum aggregate indebtedness |  |  | $ 3,000,000 |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Line of credit, covenants, basket for dispositions |  |  |  |  | $ 25,000,000
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | First Amendment |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Revolving facility usage | 1.50 |  |  |  |
Line of credit, covenants, basket for dispositions | $ 40,000,000 |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | First Amendment | Inventories |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Minimum working capital to revolving facility usage ratio | 0.50 |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | First Amendment | Accounts Receivable |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Minimum working capital to revolving facility usage ratio | 0.85 |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | First Amendment | Debt Instrument, Redemption, Period One |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Minimum leverage ratio | 3.25 |  |  |  |
Maximum liquidity ratio required | 3.50 |  |  |  |
Minimum interest coverage ratio | 1.00 |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | First Amendment | Debt Instrument, Redemption, Period Two |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Minimum leverage ratio | 3.00 |  |  |  |
Maximum liquidity ratio required | 3.25 |  |  |  |
Minimum interest coverage ratio | 1.05 |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | First Amendment | Debt Instrument, Redemption, Period Three |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Minimum leverage ratio | 2.75 |  |  |  |
Maximum liquidity ratio required | 3.00 |  |  |  |
Minimum interest coverage ratio | 1.15 |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | First Amendment | Debt Instrument, Redemption, Period Four |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Minimum interest coverage ratio | 1.25 |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Euro-rate | First Amendment |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Debt instrument, basis spread on variable rate | 1.00% |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Euro-rate | First Amendment | Minimum |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Debt instrument, basis spread on variable rate | 2.00% |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Euro-rate | First Amendment | Maximum |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Debt instrument, basis spread on variable rate | 3.00% |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Base Rate | First Amendment |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Debt instrument, basis spread on variable rate | 1.00% |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Base Rate | First Amendment | Minimum |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Debt instrument, basis spread on variable rate | 1.00% |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Base Rate | First Amendment | Maximum |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Debt instrument, basis spread on variable rate | 2.00% |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Overnight Bank Funding Rate | First Amendment |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Debt instrument, basis spread on variable rate | 0.50% |  |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Revolving credit facility |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Line of credit facility, amount outstanding |  | 844,000 |  |  |
Potential increase to borrowing capacity | $ 50,000,000 |  |  |  |
Liquidity Covenant | 25,000,000 |  |  |  |
Acquisition consideration threshold, per acquisition | 50,000,000 |  |  |  |
Aggregate acquisition threshold for four consecutive periods where acquisitions occurred | 50,000,000 |  |  |  |
Aggregate acquisition consideration threshold | 100,000,000 |  |  |  |
Line of credit facility, current borrowing capacity |  | 77,618,000 |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Revolving credit facility | First Amendment |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Line of credit facility, maximum borrowing capacity | 140,000,000 |  |  |  |
Line of credit facility, accordion feature, decrease limit | 120,000,000 |  |  |  |
Line of credit, accordion feature, lower borrowing capacity option | 25,000,000 | $ 5,000,000 |  |  |
PNC Bank, N.A., Bank of America, N.A., Wells Fargo Bank, N.A., Citizens Bank of Pennsylvania, and Branch Banking and Trust Company | Secured debt | First Amendment |  |  |  |  |
Line of Credit Facility |  |  |  |  |
Debt instrument, face amount | 25,000,000 |  |  |  |
Line of credit facility, amount outstanding | $ 22,500,000 |  |  |  |

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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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