Stockholders' Equity and Earnings Per Common Share - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Payment Arrangement, Option, Exercise Price Range, Outstanding, Weighted Average Exercise Price	$ 24.25
Outstanding Restricted Stock Unit Grant Prices Lower Limit	12.45
Outstanding Restricted Stock Unit Grant Prices Upper Limit	$ 55.26
Antidilutive Securities Excluded from Computation of Earnings Per Share	1,100,000	1,300,000
Expiration Date of Share Repurchase Program Authorized in May 2019	Nov. 23, 2020
Number of Treasury Shares Repurchased		2,700,000
Authorized Shares of Preferred Stock	25,000,000.0
Par Value Per Share of Preferred Stock	$ 0.10
Issued Shares of Preferred Stock	0
Repurchase Program Authorized in May 2019
Authorized Amount of Treasury Share Repurchases Under Stock Repurchase Program	$ 750.0
Remaining Amount of Treasury Share Repurchases Authorized Under Stock Repurchase Program	516.2
Repurchase Program Authorized in May 2018
Authorized Amount of Treasury Share Repurchases Under Stock Repurchase Program	$ 750.0
Open Market Repurchase
Cost of Shares Repurchased		$ 100.0

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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