Supplemental Cash Flow Information - Net Effects of Changes in Operating Assets and Liabilities, Net, on Cash Flows from Operating Activities (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Supplemental Cash Flow Elements [Abstract]
Accounts and notes receivable	$ 237,790	$ (56,322)	$ 360,120	$ (215,791)
Contract assets	83,677	(107,165)	100,049	(101,898)
Inventories	2,500	13,091	(1,868)	42,087
Prepaid expenses and other current assets	(33,600)	(73,235)	50,478	(102,574)
Accounts payable and accrued expenses and other non-current liabilities	22,649	44,543	(87,745)	(22,135)
Contract liabilities	19,283	67,390	6,397	44,010
Other, net	(6,591)	(123,795)	(12,253)	(129,348)
Net change in operating assets and liabilities, net of non-cash transactions	$ 325,708	(235,493)	$ 415,178	(485,649)
Payments of on-demand advance payment bonds		87,000		87,000
Payments of on-demand performance bonds		$ 25,000		$ 25,000

Payments For On-Demand Performance Bonds

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- Definition

The increase (decrease) during the reporting period of the sum of amounts due within one year (or one business cycle) from customers for the credit sale of goods and services; and from note holders for outstanding loans.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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- Definition

Amount of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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- Definition

Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

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- Definition

The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

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The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

+ References

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- Definition

The increase (decrease) during the reporting period in other obligations or expenses incurred but not yet paid.

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Amount of increase (decrease) in operating assets after deduction of operating liabilities classified as other.

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- Definition

Amount of increase (decrease) in prepaid expenses, and assets classified as other.

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- Definition

The cash outflow for the payments made by the entity, generally on a straight-line basis over periods ranging from five to forty years to developers, builders, government agencies and municipalities for borrowings received in construction.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585

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- References

No definition available.

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