Condensed Consolidated Statements of Cash Flow (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities:
Net income	$ 55,176	$ 64,327
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	74,859	73,331
Accretion of asset retirement obligation	1,545	1,323
Stock-based compensation	4,253	5,003
Amortization of deferred lease income	0	(1,344)
Income attributable to sale of tax benefits, net of interest expense	(5,538)	(6,089)
Equity in losses (earnings) of investees	(923)	(2,249)
Mark-to-market of derivative instruments	(2,043)	(1,579)
Loss on disposal of property, plant and equipment	801	1,136
Loss (gain) on severance pay fund asset	38	(547)
Deferred income tax provision	19,731	1,534
Liability for unrecognized tax benefits	666	2,709
Deferred lease revenues	0	(364)
Changes in operating assets and liabilities, net of businesses acquired:
Receivables	(24,831)	2,200
Costs and estimated earnings in excess of billings on uncompleted contracts	18,888	14,778
Inventories	(3,983)	4,224
Prepaid expenses and other	1,719	6,894
Change in operating lease right of use asset	1,865	4,176
Deposits and other	1,048	(2,284)
Accounts payable and accrued expenses	10,009	(6,196)
Billings in excess of costs and estimated earnings on uncompleted contracts	2,844	(4,272)
Liabilities for severance pay	84	64
Change in operating lease liabilities	(1,634)	0
Other long-term liabilities	(220)	(696)
Net cash provided by operating activities	154,354	156,079
Cash flows from investing activities:
Capital expenditures	(151,254)	(114,880)
Investment in unconsolidated companies	(7,759)	0
Decrease (increase) in severance pay fund asset, net of payments made to retired employees	(14)	712
Net cash used in investing activities	(159,027)	(114,168)
Cash flows from financing activities:
Proceeds from long-term loans, net of transaction costs	129,407	132,847
Repayments of commercial paper and prepayment of loans	(46,225)	(6,098)
Proceeds from revolving credit lines with banks	1,250,639	1,298,500
Repayment of revolving credit lines with banks	(1,191,132)	(1,404,400)
Cash received from noncontrolling interest	7,577	3,346
Repayments of long-term debt	(31,784)	(36,767)
Cash paid to noncontrolling interest	(3,661)	(7,828)
Payments under finance lease obligations	(1,389)	(1,713)
Deferred debt issuance costs	(677)	(4,345)
Cash dividends paid	(11,333)	(11,168)
Net cash provided by (used in) financing activities	101,422	(37,626)
Effect of exchange rate changes	(25)	(141)
Net change in cash and cash equivalents and restricted cash and cash equivalents	96,724	4,144
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	249,834	181,639
Supplemental non-cash investing and financing activities:
Increase (decrease) in accounts payable related to purchases of property, plant and equipment	$ (2,226)	$ 6,010