Condensed Consolidated Statements of Cash Flow (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net income	$ 78,274	$ 79,416
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	115,672	111,328
Accretion of asset retirement obligation	2,319	2,015
Stock-based compensation	7,060	7,231
Amortization of deferred lease income	0	(2,014)
Income attributable to sale of tax benefits, net of interest expense	(10,846)	(7,738)
Equity in losses (earnings) of investees	196	(3,334)
Mark-to-market of derivative instruments	(1,612)	(1,909)
Loss on disposal of property, plant and equipment	618	1,426
Loss (gain) on severance pay fund asset	(24)	(862)
Deferred income tax provision	25,522	7,177
Liability for unrecognized tax benefits	(2,000)	3,284
Deferred lease revenues	0	(470)
Changes in operating assets and liabilities, net of businesses acquired:
Receivables	(5,753)	(60)
Costs and estimated earnings in excess of billings on uncompleted contracts	20,242	(995)
Inventories	565	3,780
Prepaid expenses and other	2,971	4,003
Change in operating lease right of use asset	2,695	5,620
Deposits and other	(1,277)	(2,622)
Accounts payable and accrued expenses	2,617	14,237
Billings in excess of costs and estimated earnings on uncompleted contracts	4,928	(12,399)
Liabilities for severance pay	(619)	576
Change in operating lease liabilities	(2,436)	0
Other long-term liabilities	(222)	(6,238)
Net cash provided by operating activities	238,890	201,452
Cash flows from investing activities:
Capital expenditures	(231,784)	(190,530)
Investment in unconsolidated companies	(14,794)	(3,096)
Cash paid for business acquisition, net of cash acquired	(43,321)	0
Decrease (increase) in severance pay fund asset, net of payments made to retired employees	529	615
Other investing activities	(3,600)	0
Net cash used in investing activities	(292,970)	(193,011)
Cash flows from financing activities:
Proceeds from long-term loans, net of transaction costs	419,262	132,847
Proceeds from exercise of options by employees	0	2,057
Proceeds from the sale of limited liability company interest, net of transaction costs	0	58,671
Repayments of commercial paper and prepayment of loans	(50,000)	(6,098)
Proceeds from revolving credit lines with banks	1,249,400	1,311,500
Repayment of revolving credit lines with banks	(1,289,950)	(1,470,500)
Cash received from noncontrolling interest	7,577	3,346
Proceeds from issuance of commercial paper	0	50,000
Repayments of long-term debt	(115,606)	(52,997)
Cash paid to noncontrolling interest	(9,234)	(9,399)
Payments under finance lease obligations	(2,205)	(2,734)
Deferred debt issuance costs	(2,360)	(4,566)
Cash dividends paid	(16,892)	(16,774)
Net cash provided by (used in) financing activities	189,992	(4,647)
Effect of exchange rate changes	520	(1,252)
Net change in cash and cash equivalents and restricted cash and cash equivalents	136,432	2,542
Cash and cash equivalents and restricted cash and cash equivalents at beginning of period	153,110	177,495
Cash and cash equivalents and restricted cash and cash equivalents at end of period	289,542	180,037
Supplemental non-cash investing and financing activities:
Increase (decrease) in accounts payable related to purchases of property, plant and equipment	$ (995)	$ 7,496