Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	Mar. 31, 2017	Nov. 30, 2015	Jul. 31, 2014
Stockholders Equity Note [Line Items]
Par value of common stock	$ 1.00
2014 Repurchase Program
Stockholders Equity Note [Line Items]
Aggregate amount of common stock authorized for repurchase			$ 350.0
2015 Repurchase Program
Stockholders Equity Note [Line Items]
Aggregate amount of common stock authorized for repurchase		$ 400.0
Stock repurchase program, remaining share authorized for repurchase	$ 379.2