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Fair Value of Financial Instruments and Long Term Debt (Details) - USD ($) | 12 Months Ended
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Apr. 30, 2018 | Apr. 30, 2017 | Apr. 30, 2016
Debt Instrument |  |  |
Long-term debt and capital lease obligations | $ 1,277,000,000 | $ 941,000,000 |
Amount outstanding at period end | 39,600,000 | 900,000 |
Interest income | 1,583,000 | 588,000 | $ 157,000
Capitalized interest | 2,260,000 | $ 1,470,000 | $ 1,134,000
Promissory Note |  |  |
Debt Instrument |  |  |
Principal amount of each note | $ 150,000 |  |
Interest over variable Index | 1.00% |  |

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- Definition Interest Over Index + References No definition available. + 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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- Definition Amount of interest capitalized during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 + Details
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- Definition The net amount of operating interest income (expense). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.10) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
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- Definition Current portion of the total carrying amount as of the balance sheet date due within one year or the operating cycle, if longer, on all notes payable to banks paid on an installment with long term maturities. This can include the amount of any loans from the applicant firm. This does not, however, include any mortgage balances. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(a)(1),20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Details
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