XML 92 R79.htm IDEA: XBRL DOCUMENT v3.10.0.1
Commitments and Contingencies (Other Commitments and Contingencies) (Narrative) (Details) - USD ($)
$ in Millions
Jun. 30, 2018
Dec. 31, 2017
Self-Insurance [Member] | Workers' Compensation, General and Automobile Policies [Member]    
Commitments and Contingencies [Line Items]    
Self-insurance reserve $ 101.7 $ 106.2
Self-Insurance [Member] | Workers' Compensation, General and Automobile Policies [Member] | Other Long-Term Liabilities [Member]    
Commitments and Contingencies [Line Items]    
Self-insurance reserve, non-current 65.6 72.2
Self-Insurance [Member] | Workers' Compensation, General and Automobile Policies [Member] | Other Long-Term Assets [Member] | Cash [Member]    
Commitments and Contingencies [Line Items]    
Cash collateral held by insurance carriers 1.6 1.6
Self-Insurance [Member] | Employee Group Medical Claims Policies [Member]    
Commitments and Contingencies [Line Items]    
Self-insurance reserve 2.5 2.6
Performance and Payment Bonds [Member]    
Commitments and Contingencies [Line Items]    
Bonded projects, estimated costs to complete 43.8 46.0
Performance and Payment Bonds [Member] | Subsidiaries [Member]    
Commitments and Contingencies [Line Items]    
Outstanding bonds, amount 108.6 119.7
Surety Bond [Member] | Self-Insurance [Member] | Workers' Compensation [Member]    
Commitments and Contingencies [Line Items]    
Outstanding bonds, amount 15.2 15.2
Credit Facility [Member]    
Commitments and Contingencies [Line Items]    
Letters of credit issued 124.7 157.1
Credit Facility [Member] | Financial Guarantees [Member] | Self-Insurance [Member] | Workers' Compensation, General and Automobile Policies [Member]    
Commitments and Contingencies [Line Items]    
Letters of credit issued $ 87.8 $ 88.9