Quarterly report pursuant to Section 13 or 15(d)

Note 8 - Goodwill and Intangible Assets (Details Textual)

v3.20.1
Note 8 - Goodwill and Intangible Assets (Details Textual) - USD ($)
$ in Thousands
 1 Months Ended 3 Months Ended 5 Months Ended 6 Months Ended
Dec. 05, 2018
Apr. 30, 2020
Apr. 30, 2019
Apr. 30, 2019
Apr. 30, 2020
Goodwill, Impairment Loss         $ 52,740
Amortization of Intangible Assets, Total $ 700 $ 8,600 $ 7,000 $ 11,838 $ 17,147
US Concrete Pumping [Member]          
Reporting Unit, Percentage of Carrying Amount In Excess of Fair Value   6.90%     6.90%
Goodwill, Impairment Loss   $ 38,500     $ 38,500
UK Operations [Member]          
Reporting Unit, Percentage of Carrying Amount In Excess of Fair Value   14.80%     14.80%
Goodwill, Impairment Loss   $ 14,400     $ 14,400
US Concrete Waste Management Services [Member]          
Reporting Unit, Percentage of Carrying Amount In Excess of Fair Value   4.50%     4.50%
Goodwill, Impairment Loss         $ 0
Brundage-Bone Concrete Pumping, Trade Name [Member]          
Indefinite-lived Intangible Assets, Carrying Value in Excess of Fair Value, Percent   11.80%     11.80%
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)   $ 5,000     $ 5,000
Indefinite-Lived Trade Names   $ 37,300     $ 37,300
Eco-Pan, Trade Name [Member]          
Indefinite-lived Intangible Assets, Carrying Value in Excess of Fair Value, Percent   7.80%     7.80%
Indefinite-Lived Trade Names   $ 7,700     $ 7,700
Capital Pumping, Trade Name [Member]          
Indefinite-lived Intangible Assets, Carrying Value in Excess of Fair Value, Percent   109.10%     109.10%
Indefinite-Lived Trade Names   $ 5,500     $ 5,500