Stock-Based Compensation - Long-term Incentive Plans (Details) shares in Thousands	12 Months Ended
Mar. 31, 2018 shares
LTIPs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Award, Terms of Award	P2Y
Long Term Incentive Plan 2017 2018 [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, Vested and Expected to Vest, Outstanding, Number	198
Long Term Incentive Plan 2017 2018 [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	0
Options, Vested and Expected to Vest, Outstanding, Number	198
Long Term Incentive Plan 2017 2018 [Member] \| Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, Vested and Expected to Vest, Outstanding, Number	204
Long Term Incentive Plan 2016 2017 [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	173
Options, Vested and Expected to Vest, Outstanding, Number	186
Long Term Incentive Plan 2016 2017 [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	173
Options, Vested and Expected to Vest, Outstanding, Number	191
Long Term Incentive Plan 2016 2017 [Member] \| Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, Vested and Expected to Vest, Outstanding, Number	0
Long Term Incentive Plan 2015 2016 [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	102
Options, Vested and Expected to Vest, Outstanding, Number	113
Long Term Incentive Plan 2018 2019 [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, Vested and Expected to Vest, Outstanding, Number	72
Long Term Incentive Plan 2018 2019 [Member] \| Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, Vested and Expected to Vest, Outstanding, Number	72
Long Term Incentive Plan 2018 2019 [Member] \| Tranche Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, Vested and Expected to Vest, Outstanding, Number	74
Long Term Incentive Plan 2014 2015 [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, Vested and Expected to Vest, Outstanding, Number	0

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.

No definition available.

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- Definition

Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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