XML 70 R54.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Share-based Compensation (Narratives) (Details) | 3 Months Ended
--- | ---
Sep. 30, 2018 Quarter $ / shares shares | Sep. 30, 2017 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Restricted stock units granted | shares | 3,337,000 |
Stock options/units granted, grant date fair value | $ / shares | $ 6.44 |
Stock options granted | shares | 852,000 |
2014 Employee Stock Purchase Plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Shares issued under stock purchase plan | shares | 1,280,708 | 1,267,930
Weighted-average grant-date fair value of options granted (in dollars per share) | $ / shares | $ 2.73 | $ 2.41
Restricted Stock Units |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation arrangement by share-based payment award, award vesting percentage | The RSUs vest from the original grant date as to one-third (1/3) on the one-year anniversary and one-twelfth (1/12) each quarter thereafter, subject to continued service to the Company. |
Service-based Restricted Stock Units |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Restricted stock units granted, percentage | 50.00% |
VPs | Restricted Stock Units |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Restricted stock units granted | shares | 1,269,800 |
Executive Officers | Restricted Stock Units |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Restricted stock units granted | shares | 278,000 |
Other Employees | Restricted Stock Units |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Restricted stock units granted | shares | 2,067,074 |
Vice President and Chief Executive Officer | Performance Shares |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Restricted stock units granted, percentage | 50.00% |
Stock options/units granted, grant date fair value | $ / shares | $ 6.40 |
Employees | Performance Shares |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Performance stock unit vesting, earnings per share | $ / shares | $ 0.20 |
Performance stock unit vesting, consecutive quarters | Quarter | 2 |
Stock options/units vesting, stock trigger price | $ / shares | $ 10.00 |
Certain Officers and Executive Vice Presidents | Performance Stock Options |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Stock options/units granted, grant date fair value | $ / shares | 2.62 |
Stock options/units vesting, stock trigger price | $ / shares | $ 10.00 |
Stock options granted | shares | 851,700 |
Stock options vesting performance period | 3 years |
Stock options vesting, Threshold consecutive trading days from August 29, 2018 through August 31, 2021 | 30 days |
Certain Officers and Executive Vice Presidents | Performance Stock Options | Price Hurdle Met Before or on August 31, 2019 |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation arrangement by share-based payment award, award vesting percentage | one-third of the PSOs will vest on August 31, 2019 and the remainder will vest quarterly over two years. |
Award vesting percentage | 33.33% |
Certain Officers and Executive Vice Presidents | Performance Stock Options | Price Hurdle Met After August 31, 2019 |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Share-based compensation arrangement by share-based payment award, award vesting percentage | a number of the PSOs will vest (ratably calculated based upon the time elapsed between August 31, 2018 and the date the hurdle is met) and the remainder will vest quarterly through August 31, 2021. |

X
- Definition Share based compensation arrangement by share based payment award award vesting earnings per share trigger. + References No definition available. + Details
Name: | extr_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingEarningsPerShareTrigger
Namespace Prefix: | extr_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Share-based compensation arrangement by share-based payment award award vesting stock price trigger. + References No definition available. + Details
Name: | extr_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingStockPriceTrigger
Namespace Prefix: | extr_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Share based compensation arrangement by share-based payment award award vesting threshold consecutive quarters. + References No definition available. + Details
Name: | extr_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingThresholdConsecutiveQuarters
Namespace Prefix: | extr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Share-based compensation arrangement by share-based payment award award vesting threshold consecutive trading period. + References No definition available. + Details
Name: | extr_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingThresholdConsecutiveTradingPeriod
Namespace Prefix: | extr_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Share-based compensation arrangement by share-based payment award equity instruments other than options grants percentage. + References No definition available. + Details
Name: | extr_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsPercentage
Namespace Prefix: | extr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingRights
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of share instruments newly issued under a share-based compensation plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of vesting of share-based compensation awards. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_PlanNameAxis=extr_TwoThousandFourteenEmployeeStockPurchasePlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=extr_ServiceBasedRestrictedStockUnitsRSUsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TitleOfIndividualAxis=us-gaap_VicePresidentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TitleOfIndividualAxis=us-gaap_ExecutiveOfficerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TitleOfIndividualAxis=extr_OtherEmployeesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TitleOfIndividualAxis=extr_VicePresidentAndChiefExecutiveOfficerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_PerformanceSharesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TitleOfIndividualAxis=extr_EmployeesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TitleOfIndividualAxis=extr_CertainOfficersAndExecutiveVicePresidentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=extr_PerformanceStockOptionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |