Description of Business - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2019 ft² Store Segment
Description Of Business [Line Items]
Number of operating stores | Store	433
Area of traditional sporting goods store | ft²	11,000
Number of reportable segment | Segment	1
Big 5 Corp [Member]
Description Of Business [Line Items]
Subsidiary interest ownership percentage	100.00%
Big 5 Service Corp [Member] | Big 5 Corp [Member]
Description Of Business [Line Items]
Subsidiary interest ownership percentage	100.00%