Related Party Transactions	9 Months Ended
Dec. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Corporate Allocations The Statements of Operations include an allocation of general corporate expenses from Parent for certain management and support functions that are provided on a centralized basis within Parent. These management and support functions include, but are not limited to, executive management, finance, legal, IT, employee benefits administration, treasury, risk management, procurement and other shared services. These allocations were made on a direct usage basis when identifiable, with the remainder allocated on the basis of revenue, expenses, headcount or other relevant measures. These allocations were $24 million for the period from April 1 to May 31, 2018, $34 million for the three months ended December 31, 2017, and $118 million for the nine months ended December 31, 2017, and they are recorded within costs of services and selling, general and administrative in the Statements of Operations. Management of the Company and Parent consider these allocations to be a reasonable reflection of the utilization of services by, or the benefits provided to, USPS prior to the Spin-Off. These allocations may not, however, reflect the expense USPS would have incurred as a stand-alone company for the periods presented. Actual costs that may have been incurred if USPS had been a stand-alone company would depend on a number of factors, including the chosen organizational structure, what functions were outsourced or performed by employees and strategic decisions made in areas such as IT and infrastructure. Parent Company Investment Parent investment in the Balance Sheets, Statements of Cash Flows and Statements of Equity represents the Parent’s historical investment in USPS, the net effect of transactions with and allocations from Parent and USPS’s accumulated earnings prior to consummation of the Spin-Off. Transition Agreements with DXC DXC does not have an ownership interest in Perspecta following the Spin-Off, and the Company operates independently of DXC, apart from certain agreements pursuant to the Merger Agreement between Perspecta and DXC, including the Separation and Distribution Agreement (the “SDA”), and certain transition services agreements. In order to govern the ongoing relationships between the Company and DXC after the Spin-Off and to facilitate an orderly transition, the Company and DXC entered into agreements providing for various services and rights following the Spin-Off and under which the Company and DXC agreed to indemnify each other against certain liabilities arising from their respective businesses.

Related Party Transactions

Corporate Allocations

The Statements of Operations include an allocation of general corporate expenses from Parent for certain management and support functions that are provided on a centralized basis within Parent. These management and support functions include, but are not limited to, executive management, finance, legal, IT, employee benefits administration, treasury, risk management, procurement and other shared services. These allocations were made on a direct usage basis when identifiable, with the remainder allocated on the basis of revenue, expenses, headcount or other relevant measures. These allocations were $24 million for the period from April 1 to May 31, 2018, $34 million for the three months ended December 31, 2017, and $118 million for the nine months ended December 31, 2017, and they are recorded within costs of services and selling, general and administrative in the Statements of Operations.

Management of the Company and Parent consider these allocations to be a reasonable reflection of the utilization of services by, or the benefits provided to, USPS prior to the Spin-Off. These allocations may not, however, reflect the expense USPS would have incurred as a stand-alone company for the periods presented. Actual costs that may have been incurred if USPS had been a stand-alone company would depend on a number of factors, including the chosen organizational structure, what functions were outsourced or performed by employees and strategic decisions made in areas such as IT and infrastructure.

Parent Company Investment

Parent investment in the Balance Sheets, Statements of Cash Flows and Statements of Equity represents the Parent’s historical investment in USPS, the net effect of transactions with and allocations from Parent and USPS’s accumulated earnings prior to consummation of the Spin-Off.

Transition Agreements with DXC

DXC does not have an ownership interest in Perspecta following the Spin-Off, and the Company operates independently of DXC, apart from certain agreements pursuant to the Merger Agreement between Perspecta and DXC, including the Separation and Distribution Agreement (the “SDA”), and certain transition services agreements. In order to govern the ongoing relationships between the Company and DXC after the Spin-Off and to facilitate an orderly transition, the Company and DXC entered into agreements providing for various services and rights following the Spin-Off and under which the Company and DXC agreed to indemnify each other against certain liabilities arising from their respective businesses.