Share-based Compensation and Employee Benefit Plans - Defined Contribution Plans (Details)	9 Months Ended
Jun. 30, 2018
Defined Contribution Plan Disclosure [Line Items]
Company matching contribution of employee contributions up to 4% (as a percent)	100.00%
Portion of employee contribution eligible for company match, percentage of pay	4.00%
Service of one to 10 years
Defined Contribution Plan Disclosure [Line Items]
Company contribution percentage based on years of service	1.50%
Service of 11 to 20 years
Defined Contribution Plan Disclosure [Line Items]
Company contribution percentage based on years of service	3.00%
Service of 21 years and over
Defined Contribution Plan Disclosure [Line Items]
Company contribution percentage based on years of service	4.50%
Service period	21 years
Minimum \| Service of one to 10 years
Defined Contribution Plan Disclosure [Line Items]
Service period	1 year
Minimum \| Service of 11 to 20 years
Defined Contribution Plan Disclosure [Line Items]
Service period	11 years
Maximum \| Service of one to 10 years
Defined Contribution Plan Disclosure [Line Items]
Service period	10 years
Maximum \| Service of 11 to 20 years
Defined Contribution Plan Disclosure [Line Items]
Service period	20 years

The period of service used by the employer to determine the employer contribution under a defined contribution plan.

No definition available.

Name:	nexeo_DefinedContributionPlanEmployeeServicePeriod
Namespace Prefix:	nexeo_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of employees' gross pay which the employer contributes based on years of service of the employee.

+ References

No definition available.

+ Details

Name:	nexeo_DefinedContributionPlanEmployerContributionAdditionalContributionsBasedUponServicePeriod
Namespace Prefix:	nexeo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- 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

Name:	us-gaap_DefinedContributionPlanDisclosureLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_VestingAxis=nexeo_ServicePeriodOneToTenYearsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=nexeo_ServicePeriodElevenToTwentyYearsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=nexeo_ServicePeriodTwentyOneYearsAndOverMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: