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Commitments and Contingencies - Additional information (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Other Commitments [Line Items] |  |  |
Purchase orders outstanding | $ 5.4 |  |
Purchase orders outstanding, term | 3 months |  |
Performance Guarantee [Member] |  |  |
Other Commitments [Line Items] |  |  |
Bonds outstanding | $ 902.0 |  |
Estimated remaining costs for bonded projects | 399.2 |  |
Insurance Claims [Member] |  |  |
Other Commitments [Line Items] |  |  |
Insurance expense | 48.5 | $ 30.4 | $ 29.5
Contingencies Excluding Wildfire and Health Insurance [Member] |  |  |
Other Commitments [Line Items] |  |  |
Insurance coverage deductible | 1.0 |  |
Wildfire [Member] |  |  |
Other Commitments [Line Items] |  |  |
Insurance coverage deductible | 2.0 |  |
Health Insurance [Member] |  |  |
Other Commitments [Line Items] |  |  |
Insurance coverage deductible | $ 0.2 |  |

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- Definition amount of Deductible Insurance Policy for Loss Contingency + References No definition available. + Details
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- Definition The terms of arrangements in which the entity has agreed to expend funds to procure goods or services, excluding long-term purchase commitments or unconditional purchase obligations. + References No definition available. + Details
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- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248 + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349 + Details
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