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Employee Benefit Plans Investments in nonqualified plans (Details 12) - USD ($) $ in Millions | Dec. 31, 2016 | Dec. 31, 2015
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Nonqualified Defined Benefit and Contribution Plan Investments [Line Items] |  |
Investments in nonqualified benefit plans | $ 111.0 | $ 105.2
Equity securities [Member] |  |
Nonqualified Defined Benefit and Contribution Plan Investments [Line Items] |  |
Investments in nonqualified benefit plans | 62.5 | 54.2
Life insurance carried on plan participants [Member] |  |
Nonqualified Defined Benefit and Contribution Plan Investments [Line Items] |  |
Investments in nonqualified benefit plans | 35.5 | 34.3
Other investments [Member] |  |
Nonqualified Defined Benefit and Contribution Plan Investments [Line Items] |  |
Investments in nonqualified benefit plans | $ 13.0 | $ 16.7

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- Definition Investments in nonqualified benefit plans + References No definition available. + Details
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- Definition Nonqualified defined benefit and contribution plans. + References No definition available. + Details
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- Details
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- Details
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- Details
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