Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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+ Details

- Definition

The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

+ References

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+ Details

- Definition

Disclosure of the methodology and assumptions used in the reconciliation of earnings per share, which may include the individual income and share amount effects of all securities that affect earnings per share, the effect that has been given to preferred dividends in arriving at income available to common stockholders in computing basic earnings per share, securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic EPS in the future that were not included in the computation of diluted EPS because to do so would have been antidilutive for the period(s) presented and a description of any transaction that occurs after the end of the most recent period but before issuance of the financial statements that would have changed materially the number of common shares or potential common shares outstanding at the end of the period if the transaction had occurred before the end of the period.

+ References+ Details

Earnings Per Share (Narrative) (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended				3 Months Ended		12 Months Ended				3 Months Ended		12 Months Ended				12 Months Ended
	Dec. 31, 2012	Dec. 31, 2012 Restricted Stock [Member]	Dec. 31, 2011 Restricted Stock [Member]	Dec. 31, 2010 Restricted Stock [Member]	Mar. 31, 2011 Convertible Debt [Member] Original 4.0% Notes [Member]	Dec. 31, 2012 Convertible Debt [Member] Original 4.0% Notes [Member]	Dec. 31, 2012 Convertible Debt [Member] New 4.0% Notes [Member]	Dec. 31, 2011 Convertible Debt [Member] New 4.0% Notes [Member]	Mar. 31, 2011 Convertible Debt [Member] New 4.0% Notes [Member]	Dec. 31, 2010 Convertible Debt [Member] New 4.0% Notes [Member]	Mar. 31, 2011 Convertible Debt [Member] Original 4.25% Notes [Member]	Dec. 31, 2012 Convertible Debt [Member] Original 4.25% Notes [Member]	Dec. 31, 2012 Convertible Debt [Member] New 4.25% Notes [Member]	Dec. 31, 2011 Convertible Debt [Member] New 4.25% Notes [Member]	Mar. 31, 2011 Convertible Debt [Member] New 4.25% Notes [Member]	Dec. 31, 2010 Convertible Debt [Member] New 4.25% Notes [Member]	Dec. 31, 2012 Convertible Debt [Member] Total New Senior Convertible Notes [Member]	Dec. 31, 2011 Convertible Debt [Member] Total New Senior Convertible Notes [Member]	Dec. 31, 2010 Convertible Debt [Member] Total New Senior Convertible Notes [Member]
Earnings Per Share [Line Items]
Anti-dilutive common stock equivalents, shares		2,032	9,479	1,031,894
Debt instrument, exchanged amount					$ 105,300						$ 97,000
Debt instrument interest rate, stated percentage					4.00%	4.00%	4.00%		4.00%		4.25%	4.25%	4.25%		4.25%
Debt instrument, convertible, conversion price per share						$ 15.76	$ 15.76	$ 15.76		$ 15.76		$ 15.48	$ 15.48	$ 15.48		$ 15.48
Debt instrument, convertible, number of conversion shares, principal amount							6,683,000	6,683,000					6,268,000	6,268,000			13,000,000	13,000,000	13,000,000
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. Potentially dilutive common shares include 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.