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Summary of Significant Accounting and Reporting Policies (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2021 USD ($) plan shares | Dec. 31, 2020 USD ($) shares | Dec. 31, 2019 USD ($) shares
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |
Technology investments | $ 16,800,000 | $ 4,000,000 |
Decrease in the balance of technology investments | 12,800,000 |  |
Equity Investment losses were considered to be other than temporary | 0 | 0 |
Allowance for obsolete and slow moving inventories | 10,900,000 | 10,400,000 |
Depreciation expense | 76,800,000 | 82,400,000 | $ 82,300,000
Account payable, capital expenditures | 9,800,000 | 4,800,000 | 3,800,000
Advertising and promotional costs | 1,800,000 | 2,000,000 | 3,000,000
Repair and maintenance of plant and equipment | $ 24,200,000 | $ 22,600,000 | $ 28,900,000
Weighted average remaining lease term | 2 years |  |
Weighted average discount rate | 1.50% |  |
Number of shares related to stock plans not included in diluted average common shares outstanding because their effect would be antidilutive | shares | 200,037 | 403,071 | 247,855
Employee Stock Option |  |  |
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |
Number of plans | plan | 2 |  |
Minimum |  |  |
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |
Remaining lease term | 1 year |  |
Maximum |  |  |
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |
Remaining lease term | 5 years |  |
Buildings and improvements | Minimum |  |  |
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |
Minimum estimated useful life, in years | 7 years |  |
Buildings and improvements | Maximum |  |  |
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |
Minimum estimated useful life, in years | 30 years |  |
Machinery and equipment | Minimum |  |  |
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |
Minimum estimated useful life, in years | 3 years |  |
Machinery and equipment | Maximum |  |  |
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |
Minimum estimated useful life, in years | 10 years |  |

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