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v3.21.1

Related Party Transactions (Details) |  |  |  |  | 1 Months Ended | 6 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 02, 2021 USD ($) shares | Nov. 02, 2020 USD ($) shares | Oct. 14, 2020 USD ($) | Mar. 28, 2020 USD ($) | Mar. 30, 2018 USD ($) shares | Sep. 25, 2020 | Mar. 26, 2021 USD ($) | Mar. 27, 2020 USD ($) lineofcredit note | Mar. 31, 2019 USD ($) | Jun. 30, 2018 USD ($) | May 31, 2018 USD ($) | Jul. 31, 2014
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock issuance costs |  |  |  |  |  |  | $ 1,790,000 |  |  |  |  |
Total net sales |  |  |  |  |  |  | 591,207,000 | $ 650,089,000 |  |  |  |
Trade accounts receivable from related party |  |  |  |  |  |  | 23,634,000 | 30,293,000 |  |  |  |
Amounts due to related party |  |  |  |  |  |  | 2,353,000 | 4,494,000 |  |  |  |
Related party notes payable, less current portion |  |  |  |  |  |  | 0 | 17,700,000 |  |  |  |
Current portion of related party debt |  |  |  |  |  |  | 0 | 25,000,000 |  |  |  |
Noncash or part noncash divestiture, amount of consideration received |  |  |  |  |  |  | 0 | 0 |  |  |  |
Cost of goods sold |  |  |  |  |  |  | 312,305,000 | 388,813,000 |  |  |  |
Trade accounts receivable, net |  |  |  |  |  |  | 69,500,000 | 59,457,000 |  |  |  |
Sublease payments |  |  |  |  |  |  | 4,385,000 | 5,456,000 |  |  |  |
IPO - Selling Shareholders |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued in transaction (in shares) | shares | 19,332,852 | 3,750,000 |  |  |  |  |  |  |  |  |  |
IPO |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued in transaction (in shares) | shares | 0 | 28,750,000 |  |  |  |  |  |  |  |  |  |
Net proceeds | $ 0 | $ 321,425,000 |  |  |  |  |  |  |  |  |  |
Stock issuance costs |  | $ 8,450,000 |  |  |  |  |  |  |  |  |  |
Transition Services Agreement |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Fees received |  |  |  | $ 25,000 |  |  |  |  |  |  |  |
Services comparison period |  |  |  | 12 months |  |  |  |  |  |  |  |
Term of agreement |  |  |  | 12 months |  |  |  |  |  |  |  |
Annual fees payable |  |  |  | $ 50,000 |  |  |  |  |  |  |  |
Basis spread on cost |  |  |  | 10.00% |  |  |  |  |  |  |  |
Extension term |  |  |  | 12 months |  |  |  |  |  |  |  |
Period for notice of termination (at least) |  |  |  | 60 days |  |  |  |  |  |  |  |
Eliminations |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Cost of goods sold |  |  |  |  |  |  | 1,198,000 |  |  |  |  |
Trade accounts receivable, net |  |  |  | $ 3,368,000 |  |  |  |  |  |  |  |
OEP | IPO - Selling Shareholders |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued in transaction (in shares) | shares | 1,832,852 |  |  |  |  |  |  |  |  |  |  |
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 |  |  |  |  |  |  |  |
Interest payable |  |  | $ 762,000 |  |  |  | 762,000 |  |  |  |  |
Related Party Revenue |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total net sales |  |  |  |  |  |  | 104,661,000 | 184,557,000 |  |  |  |
Distribution of Sanken products |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total net sales |  |  |  |  |  |  | 0 | 35,421,000 |  |  |  |
Sanken |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Trade accounts receivable from related party |  |  |  |  |  |  | 21,595,000 | 30,293,000 |  |  |  |
Other accounts receivable from related party |  |  |  |  |  |  | 198,000 | 558,000 |  |  |  |
Purchases from related party |  |  |  |  |  |  |  | 31,917,000 |  |  |  |
Amounts due to related party |  |  |  |  |  |  |  | 4,494,000 |  |  |  |
Reimbursement of development costs |  |  |  |  |  |  | $ 0 | 1,440,000 |  |  |  |
Promissory notes outstanding |  |  |  |  |  |  |  |  | $ 30,000,000 |  |  |
Stated interest rate |  |  |  |  |  |  |  |  | 2.52% |  |  |
Interest income |  |  |  |  |  |  |  | $ 55,000 |  |  |  |
Number of notes payable | note |  |  |  |  |  |  |  | 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 |  |  |  |  |  |  |  | 1,444,000 |  |  |  |
Interest paid |  |  |  |  |  |  |  | 1,538,000 |  |  |  |
Lessee, operating terminate, period of notice |  |  |  |  |  |  | 6 months |  |  |  |  |
Sublease payments |  |  |  |  |  |  | $ 200,000 | 200,000 |  |  |  |
Sanken | SG8 Collaboration Agreement |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Reimbursement of development costs |  |  |  |  |  |  | 0 | 0 |  |  |  |
Reimbursement of development costs, percentage of costs incurred |  |  |  |  |  |  |  |  |  |  |  | 50.00%
Sanken | Related Party Revenue |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total net sales |  |  |  |  |  |  | 104,661,000 | 184,557,000 |  |  |  |
Sanken | Distribution of Sanken products |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Total net sales |  |  |  |  |  |  |  | 35,421,000 |  |  |  |
PSL |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Trade accounts receivable from related party |  |  |  | $ 3,368,000 |  |  | 767,000 |  |  |  |  |
Purchases from related party |  |  |  |  |  |  | 42,196,000 |  |  |  |  |
Amounts due to related party |  |  |  |  |  |  | 1,739,000 |  |  |  |  |
PSL | Discrete Technology Development Agreement |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Amounts due to related party |  |  |  |  |  |  | 614,000 |  |  |  |  |
PSL | IC Technology Development Agreement |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Fees received |  |  |  |  |  |  | 1,200,000 | 1,200,000 |  |  |  |
Fees paid |  |  |  |  |  |  | 1,200,000 | 1,200,000 |  |  |  |
PSL | Price Support Payment |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Purchases from related party |  |  |  |  |  |  | 5,930,000 |  |  |  |  |
PSL | PSL |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Repayments of related party notes receivable |  |  |  |  |  |  | 2,601,000 |  |  |  |  |
SEEL |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Trade accounts receivable from related party |  |  |  |  |  |  | 1,272,000 |  |  |  |  |
Director |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Monthly fee payable |  |  |  |  |  |  |  |  |  | $ 19,000 | $ 30,000 |
Signing fee |  |  |  |  | $ 54,000 |  |  |  |  |  |  |
Severance payment if terminated |  |  |  |  | $ 180,000 |  |  |  |  |  |  |
Accelerated vesting, acceleration period |  |  |  |  | 6 months |  |  |  |  |  |  |
Related party transaction amounts |  |  |  |  |  |  | 318,000 | 494,000 |  |  |  |
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 | $ 506,000 |  |  |  |

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