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Employee Benefit Plans - Asset allocations in the pension plan (Details) | May 31, 2017
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Defined Benefit Plan Disclosure [Line Items] |
Target Asset Allocations (as a percent) | 100.00%
Actual Asset Allocations (as a percent) | 100.00%
International equity |
Defined Benefit Plan Disclosure [Line Items] |
Target Asset Allocations (as a percent) | 8.00%
Actual Asset Allocations (as a percent) | 8.30%
Large cap equity |
Defined Benefit Plan Disclosure [Line Items] |
Target Asset Allocations (as a percent) | 26.00%
Actual Asset Allocations (as a percent) | 26.30%
Small cap equity |
Defined Benefit Plan Disclosure [Line Items] |
Target Asset Allocations (as a percent) | 5.00%
Actual Asset Allocations (as a percent) | 5.30%
Absolute return strategy funds |
Defined Benefit Plan Disclosure [Line Items] |
Target Asset Allocations (as a percent) | 16.00%
Actual Asset Allocations (as a percent) | 16.20%
Fixed income |
Defined Benefit Plan Disclosure [Line Items] |
Target Asset Allocations (as a percent) | 45.00%
Actual Asset Allocations (as a percent) | 43.60%
Long/short equity fund |
Defined Benefit Plan Disclosure [Line Items] |
Target Asset Allocations (as a percent) | 0.00%
Actual Asset Allocations (as a percent) | 0.30%

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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 Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5)(i) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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