Note 5 - Revisions in Estimates - Summary of Impact of Revisions in Estimates to Gross Profit (Details) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020 USD ($) $ / shares	Mar. 31, 2019 USD ($) $ / shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Range of reduction in gross profit from each project, net	$ (23,799)	$ (1,138)
Decrease to project profitability	87,248	77,111
Net loss	$ (72,538)	$ (59,761)	$ (59,761)
Diluted (in dollars per share) | $ / shares	$ (1.44)	$ (1.34)
Estimated Cost Recovery of Customer Affirmative Claims and Back Charges [Member]
Number of projects with downward estimate changes	2	2
Range of reduction in gross profit from each project, net			$ (5,000)	$ (5,000)
Decrease to project profitability	$ 28,500	$ 38,100
Net loss	$ 21,600	$ 29,400
Diluted (in dollars per share) | $ / shares	$ 0.47	$ 0.63
Estimated Cost Recovery of Customer Affirmative Claims and Back Charges [Member] | Minimum [Member]
Range of reduction in gross profit from each project, net	$ 5,800	$ 17,300
Estimated Cost Recovery of Customer Affirmative Claims and Back Charges [Member] | Maximum [Member]
Range of reduction in gross profit from each project, net	$ 22,700	$ 20,800