Number of shares repurchased under settlement of employee tax withholding obligations.

No definition available.

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Period Type:	duration

- Definition

Shares repurchased aggregate value under settlement of employee tax withholding obligations.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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CAPITAL STOCK - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended				6 Months Ended		152 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019
Equity, Class of Treasury Stock [Line Items]
Aggregate cost of repurchase	$ 0.1	$ 19.9	$ 0.1	$ 55.3
Number of shares repurchased under settlement of employee tax withholding obligations					0.2	0.1
Shares repurchased aggregate value under settlement of employee tax withholding obligations					$ 9.5	$ 5.4
2006 Share Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Share repurchase program	$ 1,000.0				$ 1,000.0		$ 1,000.0
Repurchase of shares of common stock					0.2	1.0	22.4
Aggregate cost of repurchase					$ 10.5	$ 50.0	$ 919.9