Goodwill and Acquired Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Amortization of acquired intangible assets	$ 2,775	$ 4,261	$ 7,565	$ 13,658
Arconics [Member]
Finite-Lived Intangible Assets [Line Items]
Increase in goodwill related to acquisition			2,600
Change in goodwill related to an acquisition			3,800
Increase in other intangible assets related to acquisition			$ 19,300
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Other acquired intangible assets estimated useful lives			2 years
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Other acquired intangible assets estimated useful lives			10 years