| **Goodwill and Other Intangible Assets - Table 3 (Details) (USD $)In Millions, unless otherwise specified** | 12 Months Ended                              |
|-------------------------------------------------------------------------------------------------------------|----------------------------------------------|
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| **Schedule of Amortization Expense, Intangible Assets**                                                     |                                         |   |   |
| Amortization expense                                                                                        | $ 20.3us-gaap_AmortizationOfIntangibleAssets | $ 17.3us-gaap_AmortizationOfIntangibleAssets | $ 13.4us-gaap_AmortizationOfIntangibleAssets |

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| - Definition
The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275
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