Long-Term Debt and Credit Facility - Narrative (Details)	1 Months Ended	12 Months Ended
	Oct. 31, 2015 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Oct. 31, 2017 USD ($)
Debt Instrument [Line Items]
Credit facility retired amount		$ 344,700,000
Debt issuance costs		2,517,000	$ 3,406,000
Interest expense		16,001,000	15,029,000	$ 16,044,000
Other loans payable		900,000	300,000
Other long-term debt		7,700,000	9,600,000
Long-term debt fair value		$ 356,000,000	366,000,000
Underground Solutions
Debt Instrument [Line Items]
Credit facility borrowing capacity			30,000,000
Small Acquisition
Debt Instrument [Line Items]
Credit facility borrowing capacity			3,000,000
2015 Interest Rate Swap
Debt Instrument [Line Items]
Notional amount	$ 262,500,000
Derivative fixed interest rate	1.46%
2015 Credit Facility
Debt Instrument [Line Items]
Debt instrument face amount	$ 650,000,000
Credit facility borrowing capacity					$ 350,000,000
Line of credit facility expiration period		5 years
Debt term	5 years
Payment for contract waiver				4,400,000
Debt issuance costs				1,800,000
Third party arranging fees				2,600,000
Unamortized loan costs				3,500,000
Interest expense				$ 800,000
Secure debt		$ 308,400,000	328,100,000
Proceeds from (payments on) line of credit, net		38,000,000
Letters of credit outstanding		$ 30,500,000
Line of credit outstanding			36,000,000
Amount of hedged item	$ 262,500,000
Credit facility maximum consolidated leverage ratio		3.75
Credit facility actual consolidated leverage ratio		2.97
Credit facility, remaining borrowing capacity		$ 95,300,000
Credit facility minimum consolidated fixed charge ratio		1.15
Credit facility actual consolidated fixed charge ratio		1.72
2015 Credit Facility | Insurance Carriers Collateral
Debt Instrument [Line Items]
Letters of credit outstanding		$ 13,400,000
2015 Credit Facility | Performance Guarantee
Debt Instrument [Line Items]
Letters of credit outstanding		$ 17,100,000
2015 Credit Facility | London Interbank Offered Rate (LIBOR) | Minimum
Debt Instrument [Line Items]
Debt basis spread on variable rate (as percent)		1.25%
2015 Credit Facility | London Interbank Offered Rate (LIBOR) | Maximum
Debt Instrument [Line Items]
Debt basis spread on variable rate (as percent)		2.25%
2015 Credit Facility | London Interbank Offered Rate (LIBOR) | 2015 Interest Rate Swap
Debt Instrument [Line Items]
Debt annualized rates (as percent)		3.59%
Line of Credit | 2015 Credit Facility
Debt Instrument [Line Items]
Credit facility borrowing capacity		$ 300,000,000
Proceeds from (payments on) line of credit, net		$ 2,000,000
Domestic and International | Line of Credit
Debt Instrument [Line Items]
Proceeds from (payments on) line of credit, net			$ 3,000,000