Condensed Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Revenues	$ 243,190	$ 233,391	$ 486,354	$ 449,126
Cost of Revenues	209,407	197,806	418,011	382,718
Gross Profit	33,783	35,585	68,343	66,408
Selling, General and Administrative Expenses	16,248	14,349	31,446	29,564
Amortization Expense	322	327	643	659
Operating Income	17,213	20,909	36,254	36,185
Interest and Other Expense	7,490	3,213	11,887	4,963
Income Before Provision for Income Taxes	9,723	17,696	24,367	31,222
Provision for Income Taxes	2,546	4,501	6,060	8,174
Net Income	$ 7,177	$ 13,195	$ 18,307	$ 23,048
Earnings per Common Share:
Basic (in dollars per share)	$ 0.23	$ 0.44	$ 0.60	$ 0.76
Diluted (in dollars per share)	$ 0.23	$ 0.43	$ 0.60	$ 0.75
Weighted Average Shares Outstanding:
Basic (in shares)	30,547	30,219	30,530	30,219
Diluted (in shares)	30,824	30,513	30,731	30,543