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Commitments And Contingencies (Details) - USD ($) |  | 12 Months Ended
--- | --- | ---
Oct. 01, 2020 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Commitments And Contingencies [Line Items] |  |  |  |
(Increase) decrease in prepaid and other assets |  | $ (2,122,000) | $ 1,307,000 | $ 216,000
Cotter, Jr., Derivative Litigation [Member] |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Damages sought | $ 809,000 |  |  |
Class B [Member] | Cotter Estate [Member] | Cotter, Jr. Related Litigation Matters [Member] |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Shares held by estate |  | 427,808 |  |
Voting stock percent |  | 25.50% |  |
Class B [Member] | Cotter Trust [Member] | Cotter, Jr. Related Litigation Matters [Member] |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Shares held by estate |  | 696,080 |  |
Voting stock percent |  | 41.40% |  |
Class B [Member] | Cotter Voting Trust [Member] | Cotter, Jr. Related Litigation Matters [Member] |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |
Shares held by estate |  | 1,123,888 |  |
Voting stock percent |  | 66.90% |  |

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- Definition The value (monetary amount) of the award the plaintiff seeks in the legal matter. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 + Details
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