Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Plateau Acquisition - Narrative (Details) - USD ($) $ in Thousands	Oct. 02, 2019	Mar. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Goodwill		$ 191,892	$ 191,892
Plateau Excavation
Business Acquisition [Line Items]
Total consideration	$ 427,659
Goodwill	$ 106,661