Business Segments - Schedule of Disaggregation of Net Sales by Segment (Details) - Sales Revenue, Net - Product Concentration Risk	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Sally Beauty Supply
Disaggregation Of Revenue [Line Items]
Percentage of net sales	100.00%	100.00%	100.00%	100.00%
Sally Beauty Supply | Hair color
Disaggregation Of Revenue [Line Items]
Percentage of net sales	29.10%	26.90%	28.30%	26.60%
Sally Beauty Supply | Hair care
Disaggregation Of Revenue [Line Items]
Percentage of net sales	20.50%	21.30%	20.20%	20.90%
Sally Beauty Supply | Styling tools
Disaggregation Of Revenue [Line Items]
Percentage of net sales	13.60%	14.00%	14.70%	14.70%
Sally Beauty Supply | Skin and nail care
Disaggregation Of Revenue [Line Items]
Percentage of net sales	14.60%	14.80%	14.80%	14.90%
Sally Beauty Supply | Salon supplies and accessories
Disaggregation Of Revenue [Line Items]
Percentage of net sales	7.50%	7.50%	7.30%	7.30%
Sally Beauty Supply | Multicultural products
Disaggregation Of Revenue [Line Items]
Percentage of net sales	7.00%	7.20%	6.70%	6.90%
Sally Beauty Supply | Other Beauty items
Disaggregation Of Revenue [Line Items]
Percentage of net sales	7.70%	8.30%	8.00%	8.60%
Beauty Systems Group
Disaggregation Of Revenue [Line Items]
Percentage of net sales	100.00%	100.00%	100.00%	100.00%
Beauty Systems Group | Hair color
Disaggregation Of Revenue [Line Items]
Percentage of net sales	40.30%	38.70%	39.10%	37.80%
Beauty Systems Group | Hair care
Disaggregation Of Revenue [Line Items]
Percentage of net sales	34.20%	34.00%	33.80%	33.80%
Beauty Systems Group | Styling tools
Disaggregation Of Revenue [Line Items]
Percentage of net sales	3.20%	3.70%	3.60%	4.20%
Beauty Systems Group | Skin and nail care
Disaggregation Of Revenue [Line Items]
Percentage of net sales	8.20%	8.80%	8.20%	8.90%
Beauty Systems Group | Other Beauty items
Disaggregation Of Revenue [Line Items]
Percentage of net sales	6.60%	6.60%	6.10%	6.10%
Beauty Systems Group | Promotional items
Disaggregation Of Revenue [Line Items]
Percentage of net sales	7.50%	8.20%	9.20%	9.20%