v3.20.4

Stock-based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
	Nov. 30, 2018	Oct. 31, 2020	Nov. 02, 2019	Aug. 01, 2020
Service-based Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation costs related to non-vested options		$ 0.3
Weighted-average years expected to be recognized		9 months 18 days
Total fair value of options vested		$ 2.3	$ 5.5
Expected term (years)			5 years 3 months 18 days
Risk-free interest rate			1.60%
Expected dividend yield			0.00%
Expected volatility			61.20%
Awards outstanding (in shares)		560,300		683,300
Awards outstanding (in dollars per share)		$ 77.15		$ 81.05
Omnibus Incentive Plan 2016, Amended
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares authorized (in shares)	700,000
Number of shares authorized (in shares)	4,200,000
2016 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grants under Stock Incentive Plan (in shares)		1,200,000

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