Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Income Tax [Line Items]
Valuation Allowance		$ 202,000,000	$ 129,000,000
Deferred tax liability		6,000,000	7,000,000
Unrecognized tax benefits		1,000,000	1,000,000
Unrecognized tax benefits, income tax penalties and interest expense		0
Unrecognized tax benefits, income tax penalties and interest accrued		0
Valuation allowance		5,000,000
Foreign tax credit carryforwards		5,000,000	3,000,000
Undistributed earnings		140,000,000
Provision for U.S. federal income tax		2,000,000	(14,000,000)	$ 38,000,000
Provision for state income tax			(1,000,000)	$ 4,000,000
Foreign Subsidiaries [Member]
Schedule Of Income Tax [Line Items]
Provision for U.S. federal income tax		0
Provision for state income tax		0
Domestic Country [Member]
Schedule Of Income Tax [Line Items]
Valuation Allowance		68,000,000
Operating loss carryforwards		194,000,000	$ 30,000,000
Deferred tax benefit		$ 68,000,000
Operating loss carryforwards expiration year		2036	2035
State [Member]
Schedule Of Income Tax [Line Items]
Operating loss carryforwards		$ 105,000,000	$ 35,000,000
Valuation allowance		4,000,000
Foreign Country [Member]
Schedule Of Income Tax [Line Items]
Operating loss carryforwards		26,000,000	7,000,000
Valuation allowance		$ 7,000,000
Operating Loss Carryforwards without expiration date			9,000,000
Operating Loss Carryforwards with expiration date			$ 17,000,000
Foreign Country [Member] | Maximum [Member]
Schedule Of Income Tax [Line Items]
Operating loss carryforwards expiration year		2026
Power Service [Member]
Schedule Of Income Tax [Line Items]
Deferred tax liability of intangible assets	$ 19,000,000
Deferred tax liabilities of reduction of valuation allowance	(18,000,000)
Deferred tax liability	1,000,000
Deferred tax assets, valuation allowance	$ (1,000,000)
United States [Member]
Schedule Of Income Tax [Line Items]
Valuation Allowance		$ 64,000,000
Canada (Member)
Schedule Of Income Tax [Line Items]
Valuation Allowance		7,000,000
Other Foreign Jurisdictions [Member]
Schedule Of Income Tax [Line Items]
Valuation Allowance		$ 2,000,000