Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage, All Years

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- Definition

Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage, Three to Four Years

+ References

No definition available.

+ Details

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- Definition

Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage, Two to Three Years

+ 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.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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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

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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Retirement Plans Retirement Plans - Defined Contribution Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 6.8	$ 6.1	$ 5.3
UK Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage	100.00%
UK Plan [Member] \| Maximum [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	10.00%
401k Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	62.50%
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage	8.00%
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage, Two to Three Years	33.00%
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage, Three to Four Years	66.00%
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage, All Years	100.00%
401k Plan [Member] \| Maximum [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	80.00%
401k Plan [Member] \| Minimum [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent	1.00%