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Share-Based Payments (Details 3) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Tax benefit and cash received from stock option
Tax benefit realized for stock options	$ 2.2	$ 3.4	$ 4.0
Cash received from the exercise of stock options	$ 0.8	$ 0.7	$ 2.2

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- Definition

Tax benefit and cash received from stock option.

+ References

No definition available.

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Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=SL79508275-113901

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=SL79508275-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

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