Fair Value of Financial Instruments - Senior Notes - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
4.50% Senior Notes
Fair Value Disclosure of Liabilities Not Measured at Fair Value [Line Items]
Senior notes, gross carrying amount	$ 600.0	$ 600.0
4.50% Senior Notes \| Senior Notes
Fair Value Disclosure of Liabilities Not Measured at Fair Value [Line Items]
Debt instrument, interest rate (percentage)	4.50%
Senior notes, estimated fair value	$ 539.5	534.0
6.625% Senior Notes
Fair Value Disclosure of Liabilities Not Measured at Fair Value [Line Items]
Senior notes, gross carrying amount	$ 283.5	281.2
6.625% Senior Notes \| Senior Notes
Fair Value Disclosure of Liabilities Not Measured at Fair Value [Line Items]
Debt instrument, interest rate (percentage)	6.625%
Senior notes, estimated fair value	$ 268.3	$ 280.5
Six Point Six Two Five Percent IEA Senior Notes
Fair Value Disclosure of Liabilities Not Measured at Fair Value [Line Items]
Senior notes, gross carrying amount	225.1
Six Point Six Two Five Percent MasTec Senior Notes
Fair Value Disclosure of Liabilities Not Measured at Fair Value [Line Items]
Senior notes, gross carrying amount	$ 74.9

Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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