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Amount awarded to other party in judgment or settlement of litigation.

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Amount of the obligation recognized by withdrawing from a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

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Commitments and Contingencies (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Feb. 25, 2015	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2014
Commitments and contingencies
Billings in excess of costs and estimated earnings		$ 159,120		$ 159,120		$ 112,606
Revenue		608,311	$ 507,828	1,800,978	$ 1,395,085
Gross Profit		70,421	50,129	209,957	$ 132,691
Withdrawal liability recorded		4,900		4,900
Construction Project One
Commitments and contingencies
Receivable recorded relating to the project							$ 32,900
Billings in excess of costs and estimated earnings		17,800		17,800
Construction Project Two
Commitments and contingencies
Receipts related to disputed receivable			38,000
Revenue			27,500
Gross Profit			$ 26,700
JCG \| North Texas Tollway Authority v. James Construction Group, LLC
Commitments and contingencies
Settlement	$ 17,000
Expected remediation cost	22,400
Remaining accrual balance		$ 15,400		$ 15,400
Percentage of expected costs second defendant would pay		20.00%		20.00%
Percentage of expected costs Company would pay		80.00%		80.00%
JCG \| North Texas Tollway Authority v. James Construction Group, LLC \| Maximum
Commitments and contingencies
Agreed payments by second defendant in expected remediation costs toward settlement	$ 5,400
Letters of credit
Commitments and contingencies
Total commercial letters of credit outstanding		$ 19,800		$ 19,800		16,200
Bonding
Commitments and contingencies
Bid and completion bonds issued and outstanding		$ 2,030,000		$ 2,030,000		$ 1,530,000