Contract Assets and Liabilities - Schedule of Contracts In Progress (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenue earned on uncompleted contracts	$ 755,456	$ 726,215
Less: Billings to date	(773,432)	(722,562)
Net (overbilling) underbilling	(17,976)	3,653
Costs in excess of billings and estimated earnings	39,898	44,315
Billings in excess of costs and estimated earnings	$ (57,874)	$ (40,662)

The amount of billings that were raised on the contracts to date during the period.

No definition available.

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Billings in Excess of Billings and Estimated Earnings on Uncompleted Contracts

No definition available.

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Costs in Excess of Billings and Estimated Earnings on Uncompleted Contracts

No definition available.

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The amount of Asset or liability for net Under Over billings on the contracts.

No definition available.

Name:	lmb_NetUnderOverbillingOnContracts
Namespace Prefix:	lmb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount of revenue earned from uncompleted contracts during the period.

No definition available.

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Namespace Prefix:	lmb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

No definition available.

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Balance Type:	na
Period Type:	duration