Annual report pursuant to Section 13 and 15(d)

Schedule II: Valuation and Qualifying Accounts (Details)

v3.20.4
Schedule II: Valuation and Qualifying Accounts (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Allowance for Doubtful Accounts      
Valuation And Qualifying Accounts Disclosure [Line Items]      
Balance at Beginning of Year $ 205 $ 693 $ 1,415
Additions 187 612 1,685
Deletions 340 1,100 2,677
Adjustments     270
Balance at End of Year 52 205 693
Allowance for Sales Returns      
Valuation And Qualifying Accounts Disclosure [Line Items]      
Balance at Beginning of Year 1,163 890 904
Additions 10,299 17,036 15,834
Deletions 10,720 16,763 15,848
Balance at End of Year 742 1,163 890
Allowance for Rental Revenue Adjustments      
Valuation And Qualifying Accounts Disclosure [Line Items]      
Balance at Beginning of Year 411 438 947
Additions 2,579 1,762 2,678
Deletions 2,594 1,789 2,917
Adjustments     (270)
Balance at End of Year 396 411 438
Allowance for Rental Asset Loss      
Valuation And Qualifying Accounts Disclosure [Line Items]      
Balance at Beginning of Year 395 594 754
Additions 559 188 408
Deletions 379 387 568
Balance at End of Year $ 575 $ 395 $ 594