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Fair Value Measurements - Assets and Liabilities Recorded at Fair Value (Parenthetical) (Detail) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Other Assets [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Cash flow swaps and interest rate caps designated as hedges | $ 5.1 | $ 2.8
Other Current Assets [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Cash flow swaps and interest rate caps designated as hedges | 0.9 |
Other Accrued Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Cash flow swaps designated as hedges | 1.0 | 3.7
Other Long-Term Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Cash flow swaps designated as hedges | $ 0.3 | $ 2.4

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- Definition Fair value as of the balance sheet date of all interest rate derivative assets designated as cash flow hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959 + Details
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