Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Operating activities
Net income (loss)	$ 22,847	$ (171,868)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation, depletion and amortization	81,008	84,713
Amortization related to the 2.75% Convertible Notes (see Note 13)	7,038	6,458
Gain on sales of property and equipment, net (see Note 12)	(39,349)	(4,870)
Stock-based compensation	5,181	5,203
Equity in net (income) loss from unconsolidated joint ventures	(8,027)	38,529
Net income from affiliates	(10,578)	(4,415)
Non-cash impairment charges (see Note 3)	0	156,690
Other non-cash adjustments	664	3,067
Changes in assets and liabilities:
Accrual for legal settlement (see Note 16)	129,000	0
Insurance receivable for legal settlement (see Note 16)	(63,000)	0
Receivables	(81,072)	(98,118)
Contract assets, net	(17,155)	144,558
Inventories	4,951	(13,226)
Contributions to unconsolidated construction joint ventures	(61,780)	(38,044)
Distributions from unconsolidated construction joint ventures and affiliates	14,379	9,279
Other assets, net	(102)	(6,208)
Accounts payable	47,223	(16,559)
Accrued expenses and other liabilities, net	28,694	43,477
Net cash provided by operating activities	59,922	138,666
Investing activities
Purchases of marketable securities	(5,000)	(9,996)
Maturities of marketable securities	0	10,000
Proceeds from called marketable securities	0	24,996
Purchases of property and equipment	(72,964)	(74,901)
Proceeds from sales of property and equipment (see Note 12)	58,002	12,283
Other investing activities, net	2,581	(4,283)
Net cash used in investing activities	(17,381)	(41,901)
Financing activities
Proceeds from debt	0	50,000
Debt principal repayments	(6,795)	(6,321)
Cash dividends paid	(17,846)	(17,777)
Repurchases of common stock	(2,603)	(753)
Contributions from non-controlling partners	15,701	9,250
Distributions to non-controlling partners	(3,022)	(10,060)
Other financing activities, net	(63)	324
Net cash (used in) provided by financing activities	(14,628)	24,663
Net increase in cash, cash equivalents and restricted cash	27,913	121,428
Cash, cash equivalents and $1,512 and $5,835 in restricted cash at beginning of period	437,648	268,108
Cash, cash equivalents and $1,512 in restricted cash at end of each period	465,561	389,536
Supplementary Information
Right of use assets obtained in exchange for lease obligations	13,731	9,486
Cash paid for operating lease liabilities	16,967	16,137
Cash paid during the period for:
Interest	9,215	11,966
Income taxes	1,869	2,360
Non-cash investing and financing activities:
RSUs issued, net of forfeitures	7,563	4,685
Dividends declared but not paid	5,957	5,935
Contributions from non-controlling partners	$ 9,006	$ 0