Restructuring and Asset Impairment Charges	6 Months Ended
Sep. 30, 2017
Restructuring and Related Activities [Abstract]
Restructuring and Asset Impairment Charges	Restructuring and Asset Impairment Charges Fiscal 2018 McKesson Europe Plan During the second quarter of 2018, we performed an interim impairment test of long-lived assets primarily for our U.K. retail business due to the previously discussed decline in the estimated future cash flows driven by government reimbursement reductions in the U.K. As a result, we recognized a non-cash pre-tax charge of $189 million ($157 million after-tax) to impair the carrying value of certain intangible assets (notably pharmacy licenses) and store assets (primarily fixtures). We utilized a combination of an income approach (primarily DCF model) and a market approach for estimating the fair value of intangible assets. The fair value of the intangible assets is considered a Level 3 fair value measurement due to the significance of unobservable inputs developed using company specific information. On September 29, 2017, we committed to a restructuring plan, which primarily consists of the closures of underperforming retail stores in the U.K. and a reduction in workforce. The plan is expected to be implemented prior to the end of 2018. As part of this plan, we recorded a pre-tax charge of $47 million ($40 million after-tax) primarily representing severance during the second quarter of 2018. Long-lived asset impairment and restructuring charges were recorded under the caption, “Restructuring and Asset Impairment Charges” in operating expenses in the accompanying condensed consolidated statement of operations. We expect to record total pre-tax impairment and restructuring charges of approximately $650 million to $750 million during 2018 for our McKesson Europe business, of which $586 million of pre-tax charges (including the $350 million goodwill impairment charge) were recorded during the second quarter of 2018. Estimated remaining restructuring charges primarily consist of lease termination and other exit costs. Fiscal 2016 Cost Alignment Plan In the fourth quarter of 2016, we committed to a restructuring plan to lower our operating costs (the “Cost Alignment Plan”). The Cost Alignment Plan primarily consists of a reduction in workforce, and business process initiatives that will be substantially implemented prior to the end of 2019. Business process initiatives primarily include plans to reduce operating costs of our distribution and pharmacy operations, administrative support functions, and technology platforms, as well as the disposal and abandonment of certain non-core businesses. Under the Cost Alignment Plan, we recorded total pre-tax charges of $250 million since the inception of this plan through the second quarter of 2018. The remaining charges under this program primarily consist of exit-related costs and accelerated depreciation and amortization related to our Distribution Solutions segment. There were no material restructuring charges recorded during the second quarter and first six months of 2018. In the second quarter and first six months of 2017, we recorded a pre-tax credit of $10 million and $1 million as part of the Cost Alignment Plan in operating expenses in the accompanying condensed consolidated statement of operations. We made $26 million and $71 million of cash payments, primarily related to severance. During the second quarter and first six months of 2018, we made $9 million and $23 million of cash payments, primarily related to severance. The reserve balances as of September 30, 2017 and March 31, 2017 include $59 million and $71 million recorded in other accrued liabilities, and $31 million and $35 million recorded in other noncurrent liabilities in our condensed consolidated balance sheet.

Restructuring and Asset Impairment Charges

Fiscal 2018 McKesson Europe Plan

During the second quarter of 2018, we performed an interim impairment test of long-lived assets primarily for our U.K. retail business due to the previously discussed decline in the estimated future cash flows driven by government reimbursement reductions in the U.K. As a result, we recognized a non-cash pre-tax charge of $189 million ($157 million after-tax) to impair the carrying value of certain intangible assets (notably pharmacy licenses) and store assets (primarily fixtures). We utilized a combination of an income approach (primarily DCF model) and a market approach for estimating the fair value of intangible assets. The fair value of the intangible assets is considered a Level 3 fair value measurement due to the significance of unobservable inputs developed using company specific information.

On September 29, 2017, we committed to a restructuring plan, which primarily consists of the closures of underperforming retail stores in the U.K. and a reduction in workforce. The plan is expected to be implemented prior to the end of 2018. As part of this plan, we recorded a pre-tax charge of $47 million ($40 million after-tax) primarily representing severance during the second quarter of 2018.

Long-lived asset impairment and restructuring charges were recorded under the caption, “Restructuring and Asset Impairment Charges” in operating expenses in the accompanying condensed consolidated statement of operations.

We expect to record total pre-tax impairment and restructuring charges of approximately $650 million to $750 million during 2018 for our McKesson Europe business, of which $586 million of pre-tax charges (including the $350 million goodwill impairment charge) were recorded during the second quarter of 2018. Estimated remaining restructuring charges primarily consist of lease termination and other exit costs.

Fiscal 2016 Cost Alignment Plan

In the fourth quarter of 2016, we committed to a restructuring plan to lower our operating costs (the “Cost Alignment Plan”). The Cost Alignment Plan primarily consists of a reduction in workforce, and business process initiatives that will be substantially implemented prior to the end of 2019. Business process initiatives primarily include plans to reduce operating costs of our distribution and pharmacy operations, administrative support functions, and technology platforms, as well as the disposal and abandonment of certain non-core businesses. Under the Cost Alignment Plan, we recorded total pre-tax charges of $250 million since the inception of this plan through the second quarter of 2018. The remaining charges under this program primarily consist of exit-related costs and accelerated depreciation and amortization related to our Distribution Solutions segment.

There were no material restructuring charges recorded during the second quarter and first six months of 2018. In the second quarter and first six months of 2017, we recorded a pre-tax credit of $10 million and $1 million as part of the Cost Alignment Plan in operating expenses in the accompanying condensed consolidated statement of operations. We made $26 million and $71 million of cash payments, primarily related to severance. During the second quarter and first six months of 2018, we made $9 million and $23 million of cash payments, primarily related to severance. The reserve balances as of September 30, 2017 and March 31, 2017 include $59 million and $71 million recorded in other accrued liabilities, and $31 million and $35 million recorded in other noncurrent liabilities in our condensed consolidated balance sheet.