Contracts in Process (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Contracts in Process [Line Items]
Costs and estimated earnings on uncompleted contracts	$ 1,713,230	$ 2,153,085
Less: Billings to date	1,678,977	2,142,213
Net asset position for contracts in process	$ 34,253	$ 10,872

Represents the net costs and estimated earnings in excess of billings on uncompleted contracts accounted for under the percentage-of-completion method.

No definition available.

Name:	myrg_NetCostsAndEstimatedEarningsInExcessOfBillings
Namespace Prefix:	myrg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant