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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period and Other

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)(4)

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- Definition

The cash outflow to reacquire common stock during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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- Definition

Number of shares issued during the period to an employee benefit plan, such as a defined contribution or defined benefit plan.

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- Definition

Number of share options (or share units) exercised during the current period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

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-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28,29)

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(2)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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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.

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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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- Definition

The remaining 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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- Definition

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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- Definition

Number of shares held for each class of treasury stock.

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

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Shareholders' Equity - Treasury Stock (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended			20 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	May 02, 2012
Class of Stock [Line Items]
Purchase of treasury stock	$ 2.5	$ 2.5	$ 6.5
Movement in Treasury Stock [Roll Forward]
Treasury Shares, Beginning Balance (in shares)	1,121,926us-gaap_TreasuryStockNumberOfSharesHeld	1,563,321us-gaap_TreasuryStockNumberOfSharesHeld	4,663,923us-gaap_TreasuryStockNumberOfSharesHeld
Purchases (in shares)	760,268us-gaap_TreasuryStockSharesAcquired	616,581us-gaap_TreasuryStockSharesAcquired	1,236,161us-gaap_TreasuryStockSharesAcquired
Exercise of stock options (in shares)	(87,569)	0	0
Restricted stock grants and other (in shares)	(739,408)	(622,241)	(499,851)
401(k) matching contribution (in shares)	(427,421)	(435,735)	(517,588)
Shares issued for acquisition			(3,319,324)
Treasury Shares, Ending Balance (in shares)	627,796us-gaap_TreasuryStockNumberOfSharesHeld	1,121,926us-gaap_TreasuryStockNumberOfSharesHeld	1,563,321us-gaap_TreasuryStockNumberOfSharesHeld	1,121,926us-gaap_TreasuryStockNumberOfSharesHeld
Common Stock
Class of Stock [Line Items]
Number of shares authorized to be repurchased					5,000,000
Stock repurchased during period, shares				2,600,000
Purchase of treasury stock				$ 11.6
Remaining number of shares authorized to be repurchased	2,400,000
Average price per share of treasury stock acquired and held	$ 15.31