Employee Bargaining Agreements and Benefit Plans - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) Employees Pension_Plan	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Number of temporary employees | Employees	275
Expenses for defined contribution plan	$ 12	$ 13	$ 14
Number of benefit plans, description	The company sponsors two defined benefit plans in the United Kingdom under which accrual of pension benefits have ceased. The second defined benefit plan was acquired from the John MacLean & Sons Electrical acquisition in March 2015.
Defined benefit plan, concentration risk, description	the Company’s management believes that there are no significant concentrations of risk associated with plan assets.
UK [Member]
Defined Benefit Plan Disclosure [Line Items]
Number of defined benefit plan | Pension_Plan	2
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Number of employees | Employees	4,600
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of employees collective bargaining agreement	1.00%
Net periodic benefit cost	$ 1	$ 1	$ 1
Defined benefit plan, expected future benefit payments in next twelve months	1
Defined benefit plan, expected future benefit payments in year two	1
Defined benefit plan, expected future benefit payments in year three	1
Defined benefit plan, expected future benefit payments in year four	1
Defined benefit plan, expected future benefit payments in year five	1
Defined benefit plan, expected future benefit payments in year five and thereafter	3
Defined benefit plan, expected future employer contributions, next fiscal year	$ 1