Business Segments (Reconciliation of Segment Results to Consolidated Income Before Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Business Segments [Abstract]
Income from construction operations	$ 47,227	$ 22,913
Other income, net	481	422
Interest expense	(16,436)	(16,425)
INCOME BEFORE INCOME TAXES	$ 31,272	$ 6,910

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount of income (expense) related to nonoperating activities, classified as other.

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