Business Acquisition, Contingent Consideration, Possible Number of Shares to be Issued

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- Definition

Dividend equivalents paid on restricted stock units.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Stockholders Equity Note [Line Items]

+ References

No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Fair value of contingent consideration in a business combination that is classified in shareholders' equity.

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- Definition

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

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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

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

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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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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended	9 Months Ended
	Sep. 19, 2018	Apr. 01, 2015	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Oct. 31, 2017
Stockholders Equity Note [Line Items]
Dividends declared and paid per share (usd per share)	$ 0.05		$ 0.45	$ 0.15	$ 1.35
Dividend equivalents paid				$ 0.8	$ 6.2
Common Stock
Stockholders Equity Note [Line Items]
Treasury stock, value, acquired, cost method				$ 8.6	$ 13.0
Repurchased shares for award (shares)				428,798	448,738
Average repurchase price of shares for award (usd per share)				$ 19.97	$ 29.06
Restricted Stock Units
Stockholders Equity Note [Line Items]
Restricted stock units vested and issued as common stock (shares)				1,145,849	1,095,224
Common Stock \| Stock Repurchase Program Authorized in September 2017 [Member]
Stockholders Equity Note [Line Items]
Stock repurchase program, authorized amount						$ 285.0
Treasury stock, shares, acquired (shares)				6,810,797
Treasury stock acquired, average cost per share				$ 24.85
Treasury stock, value, acquired, cost method				$ 169.2
Cogent Partners, LP
Stockholders Equity Note [Line Items]
Business acquisition, equity interest issued or issuable (in shares)		779,454
Conditional consideration (shares)		334,048
Additional Paid-in Capital \| Cogent Partners, LP
Stockholders Equity Note [Line Items]
Contingent consideration classified as equity		$ 11.9