CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Operating Activities
Net income	$ 7,947	$ 929
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation, depletion and amortization	29,502	31,331
Gain on sales of property and equipment	(1,966)	(1,286)
Stock-based compensation	8,563	4,992
Equity in net income from unconsolidated joint ventures	(5,688)	(18,547)
Gain on real estate entity	(2,452)	0
Changes in assets and liabilities:
Receivables	(87,286)	(54,262)
Costs and estimated earnings in excess of billings, net	(30,645)	(22,958)
Inventories	(9,158)	(2,102)
Contributions to unconsolidated construction joint ventures	(8,018)	(40,750)
Distributions from unconsolidated construction joint ventures	5,445	22,020
Other assets, net	(7,544)	923
Accounts payable	47,529	21,861
Accrued expenses and other current liabilities, net	(158)	1,186
Net cash used in operating activities	(53,929)	(56,663)
Investing Activities
Purchases of marketable securities	(29,894)	(29,974)
Maturities of marketable securities	20,000	16,700
Proceeds from called marketable securities	35,000	30,000
Purchases of property and equipment	(48,837)	(16,152)
Proceeds from sales of property and equipment	2,510	2,062
Other investing activities, net	(128)	912
Net cash (used in) provided by investing activities	(21,349)	3,548
Financing Activities
Long-term debt principal repayments	(2,500)	(306)
Cash dividends paid	(10,267)	(10,208)
Repurchases of common stock	(4,845)	(3,291)
Other financing activities, net	1,272	(894)
Net cash used in financing activities	(16,340)	(14,699)
Decrease in cash and cash equivalents	(91,618)	(67,814)
Cash and cash equivalents at beginning of period	252,836	255,961
Cash and cash equivalents at end of period	161,218	188,147
Cash paid during the period for:
Interest	6,911	7,220
Income taxes	6,438	412
Other non-cash operating activities:
Performance guarantees	11,247	(9,590)
Non-cash investing and financing activities:
Restricted stock units issued, net of forfeitures	21,013	6,135
Accrued cash dividends	5,148	5,118
Accrued equipment purchases	$ (5,823)	$ 3,324