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Employee Savings Plans (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Employee Savings Plans (Textual) [Abstract] |  |
Deferred compensation liability | $ 61.9 | $ 56.6
Deferred compensation liability, current | 0.8 | 0.8
Matching contributions paid | $ 6.2 | $ 5.1

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- Definition Employee savings plans. + References No definition available. + Details
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- Definition Amount of contributions made by employer into fund established for purposes of making future disbursement to individual in accordance with deferred compensation arrangement. + References No definition available. + Details
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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 25 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=6409733&loc=d3e19512-108361 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 30 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20028-108363 + Details
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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date. + References No definition available. + Details
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