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Related Party Transactions (Details) |  |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 14, 2020 USD ($) | Oct. 02, 2020 USD ($) shares | Mar. 28, 2020 USD ($) | Sep. 30, 2017 USD ($) shares | Dec. 25, 2020 USD ($) | Jun. 26, 2020 | Dec. 27, 2019 USD ($) | Dec. 25, 2020 USD ($) | Dec. 27, 2019 USD ($) | Mar. 27, 2020 USD ($) lineOfCredit notesPayable | Mar. 31, 2019 USD ($) | Jun. 30, 2018 USD ($) | May 31, 2018 USD ($)
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Total net sales |  |  |  |  | $ 164,449,000 |  | $ 159,802,000 | $ 416,099,000 | $ 475,485,000 |  |  |  |
Trade accounts receivable from related party |  |  |  |  | 19,778,000 |  |  | 19,778,000 |  | $ 30,293,000 |  |  |
Amounts due to related party |  |  |  |  | 2,078,000 |  |  | 2,078,000 |  | 4,494,000 |  |  |
Related party notes payable, less current portion |  |  |  |  | 0 |  |  | 0 |  | 17,700,000 |  |  |
Current portion of related party debt |  |  |  |  | 0 |  |  | 0 |  | 25,000,000 |  |  |
Noncash or part noncash divestiture, amount of consideration received |  |  |  |  |  |  |  | 0 | 0 |  |  |  |
Trade accounts receivable, net |  |  |  |  | 67,334,000 |  |  | 67,334,000 |  | 59,457,000 |  |  |
Stock repurchased during period, aggregate purchase price |  |  |  |  | 27,707,000 |  |  | 27,707,000 |  |  |  |  |
Common Stock, Class L |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Stock repurchased during period (in shares) | shares |  | 1,997 |  |  |  |  |  |  |  |  |  |  |
Stock repurchased during period, aggregate purchase price |  | $ 408,000 |  |  |  |  |  |  |  |  |  |  |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | PSL |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Noncash or part noncash divestiture, amount of consideration received |  |  | $ 42,700,000 |  |  |  |  |  |  |  |  |  |
Noncash or part noncash divestiture, amount of consideration transferred |  |  | $ 15,000,000 |  |  |  |  |  |  |  |  |  |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | PSL | Sanken | PSL |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Ownership percentage by majority shareholder |  |  | 70.00% |  |  |  |  |  |  |  |  |  |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | PSL | PSL |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  | 2.70% |  |  |  |  |  |  |  |  |  |
Interest paid | $ 762,000 |  |  |  |  |  |  |  |  |  |  |  |
Repayments of related party notes receivable | 51,377,000 |  |  |  |  |  |  |  |  |  |  |  |
Related party debt |  |  | $ 66,377,000 |  |  |  |  |  |  |  |  |  |
Note receivable from related party |  |  |  |  | 51,377,000 |  |  | 51,377,000 |  |  |  |  |
Interest payable | $ 762,000 |  |  |  | 762,000 |  |  | 762,000 |  |  |  |  |
Related Party Revenue |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Total net sales |  |  |  |  | 26,439,000 |  | 16,535,000 | 72,570,000 | 49,327,000 |  |  |  |
Distribution of Sanken products |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Total net sales |  |  |  |  | 0 |  | 7,666,000 | 0 | 26,688,000 |  |  |  |
Sanken |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Trade accounts receivable from related party |  |  |  |  | 17,250,000 |  |  | 17,250,000 |  | 30,293,000 |  |  |
Other accounts receivable from related party |  |  |  |  | 374,000 |  |  | 374,000 |  | 558,000 |  |  |
Purchases from related party |  |  |  |  |  |  | 7,356,000 |  | 23,835,000 |  |  |  |
Amounts due to related party |  |  |  |  |  |  |  |  |  | $ 4,494,000 |  |  |
Reimbursement of development costs |  |  |  |  | 0 |  | 360,000 | 0 | 1,080,000 |  |  |  |
Promissory notes outstanding |  |  |  |  |  |  |  |  |  |  | $ 30,000,000 |  |
Stated interest rate |  |  |  |  |  |  |  |  |  |  | 2.52% |  |
Interest income |  |  |  |  |  |  |  |  | 55,000 |  |  |  |
Number of notes payable | notesPayable |  |  |  |  |  |  |  |  |  | 3 |  |  |
Related party notes payable, less current portion |  |  |  |  |  |  |  |  |  | $ 17,700,000 |  |  |
Number of line-of-credit agreements | lineOfCredit |  |  |  |  |  |  |  |  |  | 2 |  |  |
Current portion of related party debt |  |  |  |  |  |  |  |  |  | $ 25,000,000 |  |  |
Basis spread on variable rate |  |  |  |  |  | 1.00% |  |  |  |  |  |  |
Interest expense |  |  |  |  |  |  | 334,000 |  | 1,129,000 |  |  |  |
Interest paid |  |  |  |  |  |  | 81,000 |  | 835,000 |  |  |  |
Sanken | Related Party Revenue |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Total net sales |  |  |  |  | 26,439,000 |  | 16,535,000 | 72,570,000 | 49,327,000 |  |  |  |
Sanken | Distribution of Sanken products |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Total net sales |  |  |  |  |  |  | 7,666,000 |  | 26,688,000 |  |  |  |
PSL |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Trade accounts receivable from related party |  |  | 3,368,000 |  | 2,528,000 |  |  | 2,528,000 |  |  |  |  |
Purchases from related party |  |  |  |  | 11,558,000 |  |  | 33,448,000 |  |  |  |  |
Amounts due to related party |  |  |  |  | 2,078,000 |  |  | 2,078,000 |  |  |  |  |
Reduction of intercompany balances |  |  |  |  | 1,157,000 |  |  | 1,198,000 |  |  |  |  |
PSL | Discrete Technology Development Agreement |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Fees paid |  |  |  |  | 0 |  | 0 | 0 | 0 |  |  |  |
PSL | IC Technology Development Agreement |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Fees paid |  |  |  |  | 300,000 |  |  | 900,000 |  |  |  |  |
Fees received |  |  |  |  | 300,000 |  | $ 900,000 | 300,000 | 900,000 |  |  |  |
PSL | Price Support Payment |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Purchases from related party |  |  |  |  | 1,500,000 |  |  | 5,000,000 |  |  |  |  |
PSL | Eliminations |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Accounts payable to related party |  |  | 1,198,000 |  |  |  |  |  |  |  |  |  |
Trade accounts receivable, net |  |  | $ 3,368,000 |  |  |  |  |  |  |  |  |  |
PSL | PSL |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of related party notes receivable |  |  |  |  |  |  |  | 3,368,000 |  |  |  |  |
Director |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Fees paid |  |  |  |  |  |  |  | 262,000 | $ 270,000 |  |  |  |
Monthly fee payable |  |  |  |  |  |  |  |  |  |  |  | $ 19,000 | $ 30,000
Signing fee |  |  |  | $ 54,000 |  |  |  |  |  |  |  |  |
Severance payment if terminated |  |  |  | $ 180,000 |  |  |  |  |  |  |  |  |
Accelerated vesting, acceleration period |  |  |  | 6 months |  |  |  |  |  |  |  |  |
Director | Common Stock, Class L |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Shares granted (in shares) | shares |  |  |  | 12,000,000 |  |  |  |  |  |  |  |  |
Directors and executive officers |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Related party debt |  |  |  |  | $ 0 |  |  | $ 0 |  | $ 506,000 |  |  |

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