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- Definition

The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

+ 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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Description of the general nature of multiemployer plans and of the employer's participation in those plans that would indicate how the risks of participating in these plans are different from single-employer plans. 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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=35742057&loc=SL14450655-114947

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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

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Description of the extent to which the employer could be responsible for obligations of the multiemployer plan, including benefits earned by employees during employment with another employer. 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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 7

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35742057&loc=SL14450678-114947

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- 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.

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Other Retirement Plans (Narrative) (Details) - USD ($)	12 Months Ended
Other Retirement Plans (Narrative) (Details) - USD ($)	Dec. 31, 2014	Dec. 31, 2011	Nov. 30, 2014	Dec. 31, 2013	Nov. 30, 2011
Multi-Employer Plans [Line Items]
Multi-employer plans, general nature	Certain of MasTec’s subsidiaries, including certain subsidiaries in Canada, contribute amounts to multi-employer pension and other multi-employer benefit plans and trusts, which are recorded as a component of employee wages and salaries within costs of revenue, excluding depreciation and amortization. Contributions are generally based on fixed amounts per hour per employee for employees covered under these plans. Multi-employer plan contribution rates are determined annually and assessed on a “pay-as-you-go” basis based on union employee payrolls. Union payrolls cannot be determined for future periods because the number of union employees employed at any given time, and the plans in which they may participate, vary depending upon the location and number of ongoing projects at a given time and the need for union resources in connection with those projects.
Pension [Member]
Multi-Employer Plans [Line Items]
Multi-employer plans, underfunded status, description	A multi-employer plan that is so underfunded as to be in “endangered,” “seriously endangered,” or “critical” status is required to adopt a funding improvement plan (“FIP”) or a rehabilitation plan (“RP”), which, among other actions, could include decreased benefits and increased employer contributions, which could take the form of a surcharge on benefit contributions. These actions are intended to improve their funding status over a period of years. If a pension fund is in critical status, a participating employer must pay an automatic surcharge in addition to contributions otherwise required under the collective bargaining agreement (“CBA”). With some exceptions, the surcharge is equal to 5% of required contributions for the initial critical year and 10% for each succeeding plan year in which the plan remains in critical status. The surcharge ceases on the effective date of a CBA (or other agreement) that includes contribution and benefit terms consistent with the rehabilitation plan. Certain plans in which the Company participates are in “endangered,” “seriously endangered,” or “critical” status. The amount of additional funds, if any, that the Company may be obligated to contribute to these plans in the future cannot be estimated due to the uncertainty of the future levels of work that could be required of the union employees covered by these plans, as well as the required future contribution rates and possible surcharges applicable to these plans.
Pension [Member] \| Plans from Which the Company Terminated Participation in 2014 [Member]
Multi-Employer Plans [Line Items]
Multi-employer plans, withdrawal liability (in dollars)			$ 0
Pension [Member] \| Central States Southeast and Southwest Areas Pension Fund [Member]
Multi-Employer Plans [Line Items]
Multi-employer plans, withdrawal liability (in dollars)	$ 4,200,000			$ 5,400,000	$ 6,400,000
Pension [Member] \| Central States Southeast and Southwest Areas Pension Fund [Member] \| Cost of Revenue, Excluding Depreciation and Amortization [Member] \| Withdrawal from Multi-Employer Defined Benefit Plan [Member]
Multi-Employer Plans [Line Items]
Multi-employer plans, withdrawal charge (in dollars)		$ 6,400,000
Pension [Member] \| Maximum [Member] \| Red Status [Member]
Multi-Employer Plans [Line Items]
Multi-employer plans, funded percentage	65.00%			65.00%
Pension [Member] \| Maximum [Member] \| Orange Status [Member]
Multi-Employer Plans [Line Items]
Multi-employer plans, funded percentage	70.00%			70.00%
Pension [Member] \| Maximum [Member] \| Yellow Status [Member]
Multi-Employer Plans [Line Items]
Multi-employer plans, funded percentage	80.00%			80.00%
Pension [Member] \| Minimum [Member] \| Orange Status [Member]
Multi-Employer Plans [Line Items]
Multi-employer plans, funded percentage	65.00%			65.00%
Pension [Member] \| Minimum [Member] \| Yellow Status [Member]
Multi-Employer Plans [Line Items]
Multi-employer plans, funded percentage	70.00%			70.00%
Pension [Member] \| Minimum [Member] \| Green Status [Member]
Multi-Employer Plans [Line Items]
Multi-employer plans, funded percentage	80.00%			80.00%