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Summary of Significant Accounting Policies - Product Warranties (Details) | 3 Months Ended | 15 Months Ended | 57 Months Ended
--- | --- | --- | ---
Mar. 31, 2016 | Dec. 31, 2020 | Dec. 31, 2020
Commercial LEDFL Tubular LED Lamps (Excluding Battery Backup TLED), Troffer Luminaires, And Certain Globe Lights |  |  |
Product Warranty Liability [Line Items] |  |  |
Standard Product Warranty, Number of Years |  |  | 10 years
Other LED Products |  |  |
Product Warranty Liability [Line Items] |  |  |
Standard Product Warranty, Number of Years |  | 5 years | 5 years
LEDFL Tubular LED Lamps (Excluding Red Caps) |  |  |
Product Warranty Liability [Line Items] |  |  |
Standard Product Warranty, Number of Years |  | 10 years |
Minimum |  |  |
Product Warranty Liability [Line Items] |  |  |
Standard Product Warranty, Number of Years | 1 year |  |
Minimum | D-Series Lamps |  |  |
Product Warranty Liability [Line Items] |  |  |
Standard Product Warranty, Number of Years |  | 5 years |
Maximum |  |  |
Product Warranty Liability [Line Items] |  |  |
Standard Product Warranty, Number of Years | 5 years |  |
Maximum | D-Series Lamps |  |  |
Product Warranty Liability [Line Items] |  |  |
Standard Product Warranty, Number of Years |  | 10 years |

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