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v3.8.0.1

Summary Debt Outstanding Based On Stated Maturities (Parenthetical) (Detail) | 9 Months Ended |
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Dec. 31, 2017 | Jul. 31, 2017
Bank Term Loan Due July 2019 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | July 2019 |
Revolving Line Of Credit Due July 2019 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | July 2019 |
3.90% September 2010 Senior Notes Due December 2017 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | December 2017 |
Debt instrument interest rate | 3.90% |
3.95% September 2010 Senior Notes Due December 2017 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | December 2017 |
Debt instrument interest rate | 3.95% |
4.12% September 2010 Senior Notes Due December 2018 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | December 2018 |
Debt instrument interest rate | 4.12% |
4.17% September 2010 Senior Notes Due December 2018 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | December 2018 |
Debt instrument interest rate | 4.17% |
4.33% September 2010 Senior Notes Due December 2019 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | December 2019 |
Debt instrument interest rate | 4.33% |
4.51% September 2010 Senior Notes Due December 2020 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | December 2020 |
Debt instrument interest rate | 4.51% |
4.56% September 2010 Senior Notes Due December 2020 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | December 2020 |
Debt instrument interest rate | 4.56% |
4.61% September 2010 Senior Notes Due December 2022 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | December 2022 |
Debt instrument interest rate | 4.61% |
4.06% August 2011 Senior Notes Due March 2019 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | March 2019 |
Debt instrument interest rate | 4.06% |
4.54% August 2011 Senior Notes Due June 2021 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | June 2021 |
Debt instrument interest rate | 4.54% |
4.64% August 2011 Senior Notes Due June 2021 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | June 2021 |
Debt instrument interest rate | 4.64% |
4.26% September 2013 Senior Notes Due November 2020 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | November 2020 |
Debt instrument interest rate | 4.26% |
5.01% September 2013 Senior Notes Due November 2023 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | November 2023 |
Debt instrument interest rate | 5.01% |
5.16% September 2013 Senior Notes Due November 2025 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | November 2025 |
Debt instrument interest rate | 5.16% |
8.00% New Secured Notes Due August 2022 |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | August 2022 |
Debt instrument interest rate | 8.00% | 8.00%
Norwegian Kroner Denominated Notes Due May 2024 | Troms Offshore Supply AS |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | May 2024 |
Norwegian Kroner Denominated Notes Due January 2026 | Troms Offshore Supply AS |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | January 2026 |
United States Dollar Denominated Notes Due January 2027 | Troms Offshore Supply AS |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | January 2027 |
United States Dollar Denominated Notes Due April 2027 | Troms Offshore Supply AS |  |
Debt [Line Items] |  |
Debt Instrument Maturity Period | April 2027 |

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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