Quanta Services, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Summary of Significant Accounting Policies (Revenue Recognition) - Additional Information (Detail)

v3.7.0.1

Summary of Significant Accounting Policies (Revenue Recognition) - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Revenue Recognition [Line Items]
Revenues	$ 2,178,170,000	$ 1,713,737,000
Project completion percentage	85.00%
Change orders and/or claims	$ 147,100,000		$ 137,800,000
Maximum [Member]
Revenue Recognition [Line Items]
Percent aggregate change in contract estimates impact on operating results is less than this percentage	5.00%	5.00%
Natural Gas Transmission Project That Experienced Weather Delays [Member]
Revenue Recognition [Line Items]
Losses on Contracts	$ 16,500,000
Alaska Power Plant Construction Project [Member]
Revenue Recognition [Line Items]
Losses on Contracts		$ 21,300,000
Revenue Recognized For Losses Member \| Natural Gas Transmission Project That Experienced Weather Delays [Member]
Revenue Recognition [Line Items]
Revenues	$ 0

- Definition

Percent aggregate change in contract estimates impact on operating results is less than this percentage.

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Revenue recognition.

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- Definition

Losses recognized in the current period on contracts which are expected to generate losses, which are probable and can be reasonably estimated, in a future period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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-Section S99
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- Definition

Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts.

+ References

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-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
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- Definition

The amount of costs incurred on unapproved change orders when it is probable that the cost will be recovered through a change in the contract price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Subparagraph (SX 210.5-02(3)(c)(3))
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