Represents the period of time over which company contributions vest on a pro-rata basis.

No definition available.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of employee gross pay, by the terms of the plan, that the employer may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

The amounts in accumulated other comprehensive income related to gains and losses that are not recognized immediately and are expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph s

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 158

-Paragraph 7

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (s)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

+ Details

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- Definition

The amounts in accumulated other comprehensive income related to prior service cost or credit expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

+ Details

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- Details

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- Details

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- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

+ Details

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- Definition

The amount of the aggregate benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

+ References

+ Details

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- Definition

The amount of the benefits expected to be paid in Year 5.

+ References

+ Details

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- Definition

The amount of the benefits expected to be paid in Year 4.

+ References

+ Details

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- Definition

The amount of the benefits expected to be paid in Year 1.

+ References

+ Details

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- Definition

The amount of the benefits expected to be paid in Year 3.

+ References

+ Details

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- Definition

The amount of the benefits expected to be paid in Year 2.

+ References

+ Details

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- Definition

The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6410544&loc=d3e1703-114919

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 11

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

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Employee Benefit Plans (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	May 31, 2012 Y	May 31, 2011	May 31, 2010
Defined Contribution Plan
Vesting period (in years)	3
Expense charged to results of operations	$ 13,159	$ 10,469	$ 8,065
Maximum
Defined Contribution Plan
Maximum percentage of pretax compensation that can be contributed by employees' for 401 (k) defined contribution plan	75.00%
Maximum matching contribution of employer for 401 (k) defined contribution plan (as a percent)	5.00%
Defined Benefit Pension Plans
Estimated future pension benefits
2013	8,332
2014	5,103
2015	6,568
2016	5,277
2017	5,228
2018 to 2022	30,519
Estimated amounts that will be amortized from accumulated other comprehensive loss into expense over the next fiscal year
Amortization of net actuarial loss	1,874
Amortization of prior service cost	157
Funded status
Unfunded projected benefit obligation	35,291	10,669
Domestic plans \| Minimum
Estimated future pension benefits
Anticipated contribution in next fiscal year	5,500
Domestic plans \| Maximum
Estimated future pension benefits
Anticipated contribution in next fiscal year	7,500
Postretirement Benefits Other Than Pensions
Funded status
Unfunded projected benefit obligation	$ 1,136	$ 1,187