Dividend equivalents paid on restricted stock units.

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Per Share Average Price of Shares Purchased

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No definition available.

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- Definition

Stockholders Equity Note [Line Items]

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

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- Definition

Amount of common stock allocated to investors to buy shares of a new issue of common stock before they are offered to the public. When stock is sold on a subscription basis, the issuer does not initially receive the total proceeds. In general, the issuer does not issue the shares to the investor until it receives the entire proceeds.

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Monetary value of common stock allocated to investors to buy shares of a new issue of common stock before they are offered to the public. When stock is sold on a subscription basis, the issuer does not initially receive the total proceeds. In general, the issuer does not issue the shares to the investor until it receives the entire proceeds.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
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- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of stock repurchase plan authorized.

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No definition available.

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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No definition available.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions				3 Months Ended		9 Months Ended
	Oct. 10, 2017	Sep. 27, 2017	Sep. 25, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Nov. 09, 2017
Stockholders Equity Note [Line Items]
Dividends declared and paid per share (usd per share)		$ 0.45		$ 0.45	$ 0.45	$ 1.35	$ 1.35
Dividend equivalents paid						$ 6.2	$ 6.4
Common stock, value, issued			$ 20.0
Common Stock
Stockholders Equity Note [Line Items]
Repurchased shares for award (shares)						448,738	319,194
Average repurchase price of shares for award (usd per share)						$ 29.06	$ 25.10
Treasury stock, shares, acquired (shares)							626,455
Treasury stock acquired, average cost per share							$ 20.22
Restricted Stock Units
Stockholders Equity Note [Line Items]
Restricted stock units vested and issued as common stock (shares)						1,095,224	850,387
Common Stock \| Authorized Repurchase Program on September 25 [Member]
Stockholders Equity Note [Line Items]
Treasury stock acquired, average cost per share			$ 17.00
Stock repurchase program, authorized amount			$ 235.0
Stock repurchase program, number of shares authorized to be repurchased (in shares)			9,000,000
Company's Chairman And Chief Executive Officer [Member]
Stockholders Equity Note [Line Items]
Common stock, value, issued			$ 10.0
Scenario, Forecast
Stockholders Equity Note [Line Items]
Common stock, shares issued (shares)								1,159,420
Subsequent Event
Stockholders Equity Note [Line Items]
Common stock, value, issued								$ 20.0
Subsequent Event \| Common Stock \| Authorized Repurchase Program on September 25 [Member]
Stockholders Equity Note [Line Items]
Treasury stock acquired, average cost per share	$ 17.25
Stock repurchase program, authorized amount	$ 285.0
Stock repurchase program, number of shares authorized to be repurchased (in shares)	12,000,000
Subsequent Event \| Company's Chairman And Chief Executive Officer [Member]
Stockholders Equity Note [Line Items]
Common stock, value, issued								$ 10.0
Subsequent Event \| Scenario, Forecast
Stockholders Equity Note [Line Items]
Common stock, shares issued (shares)								1,159,420