CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Operating activities
Net income (loss)	$ 59,920	$ 66,085	$ (62,448)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Restructuring (gain) impairment charges	(3,093)	1,678	93,862
Other impairment charges	3,238	5,067	821
Depreciation, depletion and amortization	56,101	60,546	74,435
Gain on sales of property and equipment	(27,447)	(15,789)	(13,748)
Change in deferred income tax	6,013	8,566	(39,289)
Stock-based compensation	11,475	12,155	13,040
Equity in income of affiliates	(1,988)	(2,193)	(756)
Changes in assets and liabilities, net of the effects of consolidations:
Receivables	9,415	(2,258)	39,070
Costs and estimated earnings in excess of billings, net	2,780	(56,524)	(35,756)
Inventories	(8,079)	43	(5,368)
Real estate held for development and sale	479	3,704	14,743
Equity in construction joint ventures	2,446	(26,313)	(8,230)
Other assets, net	9,377	(11)	6,352
Accounts payable	(9,472)	28,960	(1,871)
Accrued expenses and other current liabilities, net	(20,405)	13,844	(16,809)
Net cash provided by operating activities	91,790	92,345	29,318
Investing activities
Purchases of marketable securities	(124,596)	(155,122)	(121,626)
Maturities of marketable securities	90,100	110,875	74,000
Proceeds from sale of marketable securities	75,000	33,268	15,000
Purchase of company owned life insurance	(66)	(359)	(6,117)
Additions to property and equipment	(37,622)	(45,035)	(37,004)
Proceeds from sales of property and equipment	34,392	27,959	21,148
Purchase of private preferred stock	0	(50)	(6,400)
Other investing activities, net	(122)	736	(564)
Net cash used in investing activities	(42,554)	(27,728)	(60,435)
Financing activities
Proceeds from long-term debt	70,495	2,122	1,918
Long-term debt principal payments	(11,751)	(16,907)	(19,829)
Cash dividends paid	(20,117)	(20,117)	(20,150)
Purchase of common stock	(4,854)	(4,029)	(3,641)
Contributions from noncontrolling partners	107	519	7,321
Distributions to noncontrolling partners	(16,093)	(21,581)	(21,498)
Other financing activities, net	(2,023)	344	62
Net cash used in financing activities	15,764	(59,649)	(55,817)
Increase (decrease) in cash and cash equivalents	65,000	4,968	(86,934)
Cash and cash equivalents at beginning of year	256,990	252,022	338,956
Cash and cash equivalents at end of year	321,990	256,990	252,022
Cash paid during the period for:
Interest	11,484	16,239	15,715
Income taxes	24,616	24,783	3,861
Non-cash investing and financing activities:
Stock and restricted stock/units issued, net of forfeitures	14,175	6,874	9,192
Accrued cash dividends	5,035	5,028	5,038
Debt payments from sale of assets	1,109	14,447	6,064
Extinguishment of Debt, Amount	18,612	0	0
Short-term Debt, Refinanced, Amount	$ 1,150	$ 0	$ 0