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Employee Benefit Plans Employee Benefit Plans (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Domestic Plan |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |
Minimum Qualifying Age For Employee Benefit Plan | 21 years |  |
Expenses related to savings plan | $ 42.6 | $ 45.2 | $ 51.8
Deferred Compensation Plan |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |
Deferred compensation liability | $ 109.8 | $ 128.5 |

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- Definition Minimum qualifying age for employee benefit plan. + 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 beyond one year (or the operating cycle, if longer). + References No definition available. + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Details
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- Details
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