Earnings Per Share (Methodology) (Narrative) (Details)	6 Months Ended
Jun. 30, 2014
Earnings Per Share [Line Items]
Computation of earnings per share, methodology	Basic earnings per share is computed by dividing earnings available to MasTec’s common shareholders by the weighted average number of common shares outstanding for the period. Diluted earnings per share is computed by dividing earnings by the number of fully diluted shares, which includes the effect of dilutive potential issuances of common shares as determined using earnings from continuing operations. The potential issuance of common shares upon the exercise, conversion or vesting of outstanding stock options and unvested restricted share awards, as calculated under the treasury stock method, as well as shares associated with the Company’s outstanding convertible debt securities, may be dilutive.
Convertible Debt [Member] \| 2009 Convertible Notes [Member]
Earnings Per Share [Line Items]
Computation of earnings per share, methodology	Dilutive shares associated with the 2009 Convertible Notes are attributable to the underlying principal amounts. The number of common shares issuable upon conversion of the Company’s 2009 Convertible Notes is reflected in the calculation of weighted average diluted earnings per share for the corresponding periods by application of the “if-converted” method to the extent its effect on the computation of earnings per share from continuing operations is dilutive. Under the “if-converted” method, net income from continuing operations is adjusted to add back the after-tax amount of interest recognized for the period associated with the convertible notes, and correspondingly, the convertible notes are assumed to have been converted with the resulting common shares added to the number of weighted average shares outstanding.
Convertible Debt [Member] \| 2011 Convertible Notes [Member]
Earnings Per Share [Line Items]
Computation of earnings per share, methodology	The 2011 Convertible Notes have an optional cash settlement feature under which the Company settled the principal amount of the 2011 4.0% Notes in cash, and the Company intends to settle in cash the principal amount of the 2011 4.25% Notes. Given the Company's intention, dilutive shares associated with the 2011 Convertible Notes are derived from the premium value of the notes in excess of their principal amount, calculated using the treasury stock method. The Company refers to these shares as the "premium shares."

Earnings Per Share (Methodology) (Narrative) (Details)

6 Months Ended

Jun. 30, 2014

Computation of earnings per share, methodology

Basic earnings per share is computed by dividing earnings available to MasTec’s common shareholders by the weighted average number of common shares outstanding for the period. Diluted earnings per share is computed by dividing earnings by the number of fully diluted shares, which includes the effect of dilutive potential issuances of common shares as determined using earnings from continuing operations. The potential issuance of common shares upon the exercise, conversion or vesting of outstanding stock options and unvested restricted share awards, as calculated under the treasury stock method, as well as shares associated with the Company’s outstanding convertible debt securities, may be dilutive.

Convertible Debt [Member] | 2009 Convertible Notes [Member]

Earnings Per Share [Line Items]

Computation of earnings per share, methodology

Dilutive shares associated with the 2009 Convertible Notes are attributable to the underlying principal amounts. The number of common shares issuable upon conversion of the Company’s 2009 Convertible Notes is reflected in the calculation of weighted average diluted earnings per share for the corresponding periods by application of the “if-converted” method to the extent its effect on the computation of earnings per share from continuing operations is dilutive. Under the “if-converted” method, net income from continuing operations is adjusted to add back the after-tax amount of interest recognized for the period associated with the convertible notes, and correspondingly, the convertible notes are assumed to have been converted with the resulting common shares added to the number of weighted average shares outstanding.

Convertible Debt [Member] | 2011 Convertible Notes [Member]

Earnings Per Share [Line Items]

Computation of earnings per share, methodology

The 2011 Convertible Notes have an optional cash settlement feature under which the Company settled the principal amount of the 2011 4.0% Notes in cash, and the Company intends to settle in cash the principal amount of the 2011 4.25% Notes. Given the Company's intention, dilutive shares associated with the 2011 Convertible Notes are derived from the premium value of the notes in excess of their principal amount, calculated using the treasury stock method. The Company refers to these shares as the "premium shares."