Assets Held for Sale and Discontinued Operations - Schedule of Discontinued Operations, Balance Sheet (Details) - USD ($) $ in Thousands	Apr. 30, 2021	Jan. 31, 2021
Current assets of discontinued operations:
Total current assets of discontinued operations	$ 4,086	$ 4,321
Current liabilities of discontinued operations:
Total current liabilities of discontinued operations	972	963
Discontinued Operations, Held-for-sale
Current assets of discontinued operations:
Accounts receivable, net	1,310	1,668
Inventories, net	47	352
Prepaid expenses and other current assets	340	150
Seismic equipment lease pool and property and equipment, net	2,389	2,151
Total current assets of discontinued operations	4,086	4,321
Current liabilities of discontinued operations:
Accounts payable	13	59
Deferred revenue	73	73
Accrued expenses and other current liabilities	915	831
Income taxes payable (receivable)	(29)	0
Total current liabilities of discontinued operations	$ 972	$ 963