Multiemployer Plans, Number of Plans

No definition available.

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Period Type:	instant

- Definition

Amount of contributions made to multiemployer plan by employer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947

+ Details

Name:	us-gaap_MultiemployerPlanContributionsByEmployer
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Indicate whether the multiemployer plan is less than 65 percent funded, between 65 and less than 80 percent funded, or at least 80 percent funded. The acceptable values are: (1) "less than 65 percent", (2) "between 65 and less than 80 percent", (3) "at least 80 percent", and (4) "NA". A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947

+ Details

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Data Type:	us-types:fundedStatusItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of the obligation recognized by withdrawing from a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Details

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- Details

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Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_RetirementPlanSponsorLocationAxis=us-gaap_ForeignPlanMember
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Data Type:	na
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- Details

Name:	us-gaap_MultiemployerPlanPlanInformationAxis=us-gaap_MultiemployerPlanPlanInformationNotAvailableMember
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- Details

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- Details

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- Details

Name:	us-gaap_MultiemployerPlanTypeAxis=us-gaap_MultiemployerPlansPostretirementBenefitMember
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Data Type:	na
Balance Type:
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- Details

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- Details

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- Details

Name:	us-gaap_MultiemployerPlanNameAxis=eme_UkPlan1Member
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Multiemployer Plans - Narrative (Details)	12 Months Ended
Multiemployer Plans - Narrative (Details)	Dec. 31, 2018 USD ($) plan	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Multiemployer Plans [Line Items]
Withdrawal liability	$ 0	$ 0	$ 0
Minimum \| Multiemployer Plans, Pension
Multiemployer Plans [Line Items]
Number of plans \| plan	200
UK Plan \| Multiemployer Plans, Pension \| Multiemployer Plan, Plan Information, Not Available
Multiemployer Plans [Line Items]
Number of plans \| plan	2
Contributions	$ 100,000	100,000	200,000
UNITED STATES \| Multiemployer Plans, Pension \| Multiemployer Plan, Plan Information, Available
Multiemployer Plans [Line Items]
Contributions	190,229,000	179,216,000	167,297,000
UNITED STATES \| Multiemployer Plans, Postretirement Benefit \| Multiemployer Plan, Plan Information, Not Available
Multiemployer Plans [Line Items]
Contributions	135,900,000	$ 130,900,000	$ 130,500,000
UNITED STATES \| Minimum \| Multiemployer Plans, Pension \| Multiemployer Plan, Plan Information, Available
Multiemployer Plans [Line Items]
Contributions	2,000,000
Red Zone \| UNITED STATES \| Minimum \| Multiemployer Plans, Pension \| Multiemployer Plan, Plan Information, Available
Multiemployer Plans [Line Items]
Contributions	500,000
Orange or Yellow Zones \| UNITED STATES \| Minimum \| Multiemployer Plans, Pension \| Multiemployer Plan, Plan Information, Available
Multiemployer Plans [Line Items]
Contributions	$ 1,000,000
UK Plan 1 \| UK Plan \| Multiemployer Plans, Pension \| Multiemployer Plan, Plan Information, Not Available
Multiemployer Plans [Line Items]
Multiemployer plans, funded status	At least 80 percent