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Fair Value Measurements - Summary of Company's Financial Assets and Liabilities that were Accounted for at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions | Mar. 31, 2016 | Mar. 31, 2015
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Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate swap contracts included in Accounts Payable | $ 3.7 | $ 3.1
Fair Value Measurements, Recurring [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate swap contracts included in Accounts Payable | 3.7 |
Total Liabilities | 3.7 |
Level 2 [Member] | Fair Value Measurements, Recurring [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Interest rate swap contracts included in Accounts Payable | 3.7 |
Total Liabilities | $ 3.7 |

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- Definition Fair value of financial and nonfinancial obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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