Employee Benefits - Additional Information (Detail) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2017
Defined Contribution and Other Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contribution to the plan	$ 5,000,000
Contribution to other postretirement plans	2,200,000
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Decrease in pension expense		$ 8,000,000
U.S. Plans | Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to the plans	0
U.S. Plans | Minimum | Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contribution to the plan	2,000,000
U.S. Plans | Maximum | Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contribution to the plan	10,000,000
Non-U.S. Plans | Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to the plans	29,300,000
Non-U.S. Plans | Non-Qualified U.S. Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to the plans	$ 2,200,000