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Summary of Significant Accounting and Reporting Policies (Narrative) (Details) |  |  | 12 Months Ended |
--- | --- | --- | --- | ---
Dec. 31, 2014 | Dec. 05, 2014 | Dec. 31, 2016 USD ($) plan shares | Dec. 31, 2015 USD ($) shares | Dec. 31, 2014 USD ($) shares | Mar. 31, 2016 USD ($)
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |  |  |  |
Allowance for obsolete and slow moving inventories |  |  | $ 6,100,000 | $ 8,200,000 |  |
Depreciation expense |  |  | 66,300,000 | 58,100,000 | $ 55,300,000 |
Advertising and promotional costs |  |  | 1,900,000 | 1,400,000 | 1,100,000 |
Repair and maintenance of plant and equipment |  |  | $ 22,100,000 | $ 20,700,000 | $ 17,900,000 |
Shares related to stock plans not included in diluted average common shares outstanding because their effect would be antidilutive | shares |  |  | 1,985,849 | 1,656,936 | 1,228,694 |
Deferred tax assets, current |  |  | $ 0 | $ (24,366,588) |  |
Deferred tax liability, non-current |  |  | 71,212,620 | 69,524,621 |  |
Tax benefits associated with the exercise, vesting or disposition of stock under stock plans recognized as an adjustment of additional paid-in capital |  |  | 11,800,000 | 5,000,000 | $ 10,800,000 |
Accounting Standards Update 2016-09 [Member] |  |  |  |  |  |
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |  |  |  |
Tax benefits associated with the exercise, vesting or disposition of stock under stock plans recognized as an adjustment of additional paid-in capital |  |  | $ 4,300,000 | $ 2,300,000 | $ 5,000,000 |
Accounting Standards Update 2015-17 [Member] |  |  |  |  |  |
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |  |  |  |
Deferred tax liability, non-current |  |  |  |  |  | $ 27,000,000
Common Stocks |  |  |  |  |  |
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |  |  |  |
Common stock split conversion ratio | 2 | 2 |  |  |  |
Common stock split, stock dividend percent | 100.00% | 100.00% |  |  |  |
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 |  |  |
Employee Stock Option [Member] |  |  |  |  |  |
Summary Of Significant Accounting And Reporting Policies [Line Items] |  |  |  |  |  |
Number of plans | plan |  |  | 2 |  |  |

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