| Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] |
| | | | | (in thousands, except share and per share amounts) | | Three Months Ended January 31, 2020 | | | December 6, 2018 through January 31, 2019 | | | Net loss (numerator): | | | | | | | | | | Net loss attributable to Concrete Pumping Holdings, Inc. | | $ | (2,746 | ) | | $ | (3,630 | ) | | Less: Undistributed earnings allocated to participating securities | | | - | | | | - | | | Less: Accretion of liquidation preference on preferred stock | | | (473 | ) | | | (269 | ) | | Net loss attributable to common stockholders (numerator for basic earnings per share) | | $ | (3,219 | ) | | $ | (3,899 | ) | | | | | | | | | | | | Weighted average shares (denominator): | | | | | | | | | | Weighted average shares - basic | | | 52,629,214 | | | | 28,847,707 | | | Weighted average shares - diluted | | | 52,629,214 | | | | 28,847,707 | | | | | | | | | | | | | Basic loss per share | | $ | (0.06 | ) | | $ | (0.14 | ) | | Diluted loss per share | | $ | (0.06 | ) | | $ | (0.14 | ) | | | | | | (in thousands, except share and per share amounts) | | November 1, 2018 through December 5, 2018 | | | Net loss (numerator): | | | | | | Net loss income attributable to Concrete Pumping Holdings, Inc. | | $ | (22,575 | ) | | Less: Accretion of liquidation preference on preferred stock | | | (126 | ) | | Less: Undistributed earnings allocated to preferred shares | | | - | | | Net (loss) available to common shareholders | | $ | (22,701 | ) | | | | | | | | Weighted average shares (denominator): | | | | | | Weighted average shares - basic | | | 7,576,289 | | | Weighted average shares - diluted | | | 7,576,289 | | | | | | | | | Antidilutive stock options | | | 932,746 | | | | | | | | | Basic loss per share | | $ | (3.00 | ) | | Diluted loss per share | | $ | (3.00 | ) | |