Revenue (Schedule of Revenue Disaggregation by Product Category) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2021	Aug. 01, 2020	Jul. 31, 2021	Aug. 01, 2020
Disaggregation Of Revenue [Line Items]
Net sales	$ 332,230	$ 300,794	$ 660,687	$ 448,289
Sales Revenue Net [Member] | Geographic Concentration Risk [Member]
Disaggregation Of Revenue [Line Items]
Percentage of net sales	100.00%	100.00%	100.00%	100.00%
Net sales	$ 332,230	$ 300,794	$ 660,687	$ 448,289
Sales Revenue Net [Member] | Geographic Concentration Risk [Member] | Non-Athletics [Member]
Disaggregation Of Revenue [Line Items]
Percentage of net sales	48.00%	42.00%	46.00%	40.00%
Net sales	$ 157,372	$ 124,030	$ 300,478	$ 178,675
Sales Revenue Net [Member] | Geographic Concentration Risk [Member] | Non-Athletics [Member] | Women's [Member]
Disaggregation Of Revenue [Line Items]
Percentage of net sales	25.00%	22.00%	24.00%	21.00%
Net sales	$ 83,141	$ 65,167	$ 158,672	$ 94,088
Sales Revenue Net [Member] | Geographic Concentration Risk [Member] | Non-Athletics [Member] | Men's [Member]
Disaggregation Of Revenue [Line Items]
Percentage of net sales	16.00%	14.00%	15.00%	14.00%
Net sales	$ 51,678	$ 42,319	$ 95,960	$ 61,034
Sales Revenue Net [Member] | Geographic Concentration Risk [Member] | Non-Athletics [Member] | Children's [Member]
Disaggregation Of Revenue [Line Items]
Percentage of net sales	7.00%	6.00%	7.00%	5.00%
Net sales	$ 22,553	$ 16,544	$ 45,846	$ 23,553
Sales Revenue Net [Member] | Geographic Concentration Risk [Member] | Athletics [Member]
Disaggregation Of Revenue [Line Items]
Percentage of net sales	47.00%	53.00%	48.00%	55.00%
Net sales	$ 156,475	$ 160,319	$ 323,372	$ 245,355
Sales Revenue Net [Member] | Geographic Concentration Risk [Member] | Athletics [Member] | Women's [Member]
Disaggregation Of Revenue [Line Items]
Percentage of net sales	15.00%	19.00%	16.00%	20.00%
Net sales	$ 49,648	$ 55,961	$ 108,243	$ 88,873
Sales Revenue Net [Member] | Geographic Concentration Risk [Member] | Athletics [Member] | Men's [Member]
Disaggregation Of Revenue [Line Items]
Percentage of net sales	20.00%	24.00%	20.00%	23.00%
Net sales	$ 66,902	$ 72,941	$ 132,626	$ 104,401
Sales Revenue Net [Member] | Geographic Concentration Risk [Member] | Athletics [Member] | Children's [Member]
Disaggregation Of Revenue [Line Items]
Percentage of net sales	12.00%	10.00%	12.00%	12.00%
Net sales	$ 39,925	$ 31,417	$ 82,503	$ 52,081
Sales Revenue Net [Member] | Geographic Concentration Risk [Member] | Accessories and Other [Member]
Disaggregation Of Revenue [Line Items]
Percentage of net sales	5.00%	5.00%	6.00%	5.00%
Net sales	$ 18,383	$ 16,445	$ 36,837	$ 24,259