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Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions | Apr. 01, 2018 | Dec. 31, 2017
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Persol Holdings Investment |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cost of available-for-sale investments | $ 19.5 | $ 18.4

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- Definition This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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