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Summary of Significant Accounting Policies - Additional Information (Details) |  |  |  | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jul. 02, 2020 USD ($) | Jul. 19, 2018 USD ($) | Jul. 05, 2011 patent | Jul. 31, 2015 patent | Dec. 31, 2020 USD ($) Reporting_Unit | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Jan. 01, 2020 USD ($) | Dec. 31, 2017 USD ($)
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Amount of inventory as a percentage of prior year purchases that can be returned by certain distributors |  |  |  |  | 3.00% |  |  |  |
Unprocessed adjustments recognized against gross accounts receivables |  |  |  |  | $ 25,500,000 | $ 29,500,000 |  |  |
Unprocessed adjustments recognized against accounts accrued liabilities |  |  |  |  | 13,000,000.0 | 11,000,000.0 |  |  |
Bad debt expense, net of recoveries |  |  |  |  | 2,400,000 | 100,000 | $ 200,000 |  |
Allowance for doubtful accounts |  |  |  |  | 5,100,000 | 2,600,000 |  |  |
Obsolescence and other reserves |  |  |  |  | $ 32,269,000 | 21,245,000 |  |  |
Number of reporting units used in quantitative assessment | Reporting_Unit |  |  |  |  | 10 |  |  |  |
Goodwill impairment loss |  |  |  |  | $ 0 | 0 | 0 |  |
Gain on disposal |  |  |  |  | (9,948,000) | 0 | 0 |  |
Accumulated other comprehensive losses recognized as result of sale of equity method investment |  |  |  |  | 191,851,000 | 63,418,000 |  |  |
Proceeds from disposal of business, net of cash sold |  |  |  |  | 54,821,000 | 0 | 40,171,000 |  |
Accrued sales rebates |  |  |  |  | 32,192,000 | 37,170,000 |  |  |
Gain from patent litigation |  |  |  |  | 0 | 0 | 62,141,000 |  |
Advertising costs |  |  |  |  | 11,600,000 | 14,700,000 | 17,000,000.0 |  |
Valuation allowances |  |  |  |  | 84,308,000 | 48,251,000 |  |  |
Cumulative effect of change in accounting principle |  |  |  |  | (757,051,000) | (965,819,000) | (1,387,588,000) |  | $ (1,434,866,000)
Net Operating Losses, Capital Losses and Foreign Tax Credits |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Valuation allowances |  |  |  |  | 84,300,000 |  |  |  |
Retained Earnings |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Cumulative effect of change in accounting principle |  |  |  |  | (450,876,000) | (518,004,000) | (922,000,000) |  | (833,610,000)
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Cumulative effect of change in accounting principle |  |  |  |  |  | 2,916,000 | 29,041,000 |  |
Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Cumulative effect of change in accounting principle |  |  |  |  |  | 2,916,000 | 29,041,000 | $ 2,900,000 |
Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings | Continuing Operations |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Cumulative effect of change in accounting principle |  |  |  |  |  |  |  | 1,000,000.0 |
Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings | Discontinued Operations |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Cumulative effect of change in accounting principle |  |  |  |  |  |  |  | 1,900,000 |
Subsidiaries | Corning |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Number of patents allegedly infringed upon | patent |  |  | 2 |  |  |  |  |  |
Proceeds from settlement |  | $ 62,100,000 |  |  |  |  |  |  |
Number of patents found infringed upon | patent |  |  |  | 2 |  |  |  |  |
Grass Valley |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Impairment of the disposal group |  |  |  |  | 113,000,000.0 | 521,400,000 |  |  |
Grass Valley | Discontinued Operations, Disposed of by Sale |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Proceeds from disposal of business, net of cash sold | $ 56,200,000 |  |  |  |  |  |  |  |
Grass Valley | Discontinued Operations, Held-for-sale |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Goodwill impairment loss |  |  |  |  |  | 326,100,000 |  |  |
Impairment of the disposal group |  |  |  |  | 113,007,000 | $ 521,441,000 | 0 |  |
Previously Closed Operating Facility | Discontinued Operations, Disposed of by Sale |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Disposition, sales price |  |  |  |  | 2,100,000 |  | 1,500,000 |  |
Gain on disposal |  |  |  |  | $ 400,000 |  | 600,000 |  |
Hirschmann Jv | Discontinued Operations, Held-for-sale |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Disposition, sales price |  |  |  |  |  |  |  |  | $ 40,200,000
Proceeds from disposal of business, net of cash sold |  |  |  |  |  |  | $ 40,200,000 |  |
Minimum |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Estimated useful life of definite-lived intangible assets |  |  |  |  | 1 year |  |  |  |
Maximum |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Estimated useful life of definite-lived intangible assets |  |  |  |  | 25 years |  |  |  |
Buildings | Minimum |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Estimated useful life of property, plant, and equipment |  |  |  |  | 10 |  |  |  |
Buildings | Maximum |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Estimated useful life of property, plant, and equipment |  |  |  |  | 40 years |  |  |  |
Machinery and equipment | Minimum |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Estimated useful life of property, plant, and equipment |  |  |  |  | 5 |  |  |  |
Machinery and equipment | Maximum |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Estimated useful life of property, plant, and equipment |  |  |  |  | 12 years |  |  |  |
Computer Equipment and Software | Minimum |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Estimated useful life of property, plant, and equipment |  |  |  |  | 5 |  |  |  |
Computer Equipment and Software | Maximum |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Estimated useful life of property, plant, and equipment |  |  |  |  | 10 years |  |  |  |
Accounting Standards Update 2016-13 | Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings | Continuing Operations |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Cumulative effect of change in accounting principle |  |  |  |  |  |  |  | 1,000,000.0 |
Accounting Standards Update 2016-13 | Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings | Discontinued Operations |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Cumulative effect of change in accounting principle |  |  |  |  |  |  |  | $ 1,900,000 |
Hirschmann Jv |  |  |  |  |  |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Equity method investment, ownership percentage |  |  |  |  |  |  |  |  | 50.00%

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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(30)(a)(4)) -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 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(23)(a)(3)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669686-108580 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(2)(ii) -URI http://asc.fasb.org/extlink&oid=121370832&loc=SL117420844-207641 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e681-108580 + Details
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