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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Price of a single share of a number of saleable stocks of a company.

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Amount of stock repurchase plan authorized.

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Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of stockholders participating in a share repurchase and retirement transaction.

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EARNINGS PER SHARE - Restricted Stock Awards and Share Repurchases (Detail) $ / shares in Units, $ in Thousands, shares in Millions	1 Months Ended		3 Months Ended	12 Months Ended
	Feb. 28, 2018 $ / shares	Feb. 28, 2017 USD ($)	Mar. 31, 2015 USD ($) shareholder $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Feb. 23, 2018 USD ($)
Repurchases of common stock
Reduction of equity for retirement of repurchased shares				$ 34,899	$ 12,893	$ 50,261
Subsequent Event
Dividends
Dividend declared per share \| $ / shares	$ 0.25
Restricted shares
Repurchases of common stock
Repurchased and retired shares \| shares				0.2	0.2	0.2
Weighted average market price of shares repurchased and retired (in dollars per share) \| $ / shares				$ 41.21	$ 22.74	$ 20.11
RSUs
Repurchases of common stock
Repurchased and retired shares \| shares				0.3	0.0	0.0
Weighted average market price of shares repurchased and retired (in dollars per share) \| $ / shares				$ 39.82
Common shares
Repurchases of common stock
Repurchased and retired shares \| shares			3.0
Number of stockholders participating in a share repurchase and retirement transaction \| shareholder			1
Price paid per share for repurchased common stock \| $ / shares			$ 15.60
Reduction of equity for retirement of repurchased shares			$ 46,800
Share repurchase program 2016
Repurchases of common stock
Reduction of equity for retirement of repurchased shares					$ 9,200
Share repurchase program 2016 \| Common shares
Repurchases of common stock
Repurchased and retired shares \| shares					0.4
Weighted average market price of shares repurchased and retired (in dollars per share) \| $ / shares					$ 23.11
Authorized share repurchase capacity remaining				$ 59,000
Share repurchase program 2017 \| Common shares
Repurchases of common stock
Repurchased and retired shares \| shares				0.3
Weighted average market price of shares repurchased and retired (in dollars per share) \| $ / shares				$ 47.10
Reduction of equity for retirement of repurchased shares				$ 16,000
Repurchase authorization		$ 75,000
Share repurchase program, period for repurchases		12 months
Share repurchase program 2018 \| Common shares
Repurchases of common stock
Repurchase authorization							$ 50,000
Share repurchase program, period for repurchases	12 months