Derivative Instruments	12 Months Ended
Mar. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments In the normal course of business, the Company is exposed to interest rate fluctuations. As part of its risk management strategy, the Company uses derivative instruments, primarily interest rate swaps, to hedge certain interest rate exposures. The Company’s objective is to add stability to interest expense and to manage its exposure to movements in market interest rates. The Company does not use derivative instruments for trading or any speculative purpose. Derivatives Designated for Hedge Accounting The Company uses interest rate swap agreements designated as cash flow hedges to mitigate its exposure to interest rate risk associated with the variability of cash outflows for interest payments on certain floating interest rate debt, which effectively converted the debt into fixed interest rate debt. The Company entered into $1.4 billion of notional interest rate swap agreements concurrently with its Credit Facilities (as defined under Note 12 – “Debt”), on May 31, 2018, and $200 million of notional interest rate swap agreements in October 2018. As of March 31, 2019, the Company had interest rate swap agreements with a total notional amount of $1.6 billion. The Company initially accounted for all changes in fair value of its interest rate swaps on the statements of operations until designation as a cash flow hedge of interest rate risk on June 22, 2018. As a result, the Company recorded a gain of $5 million in the first quarter, included in interest expense, net on the statement of operations for the fiscal year ended March 31, 2019. Following the June 22, 2018 cash flow hedge designation, all changes in the hedging instruments’ fair value are recorded in accumulated other comprehensive loss (“AOCL”) and subsequently reclassified into earnings in the period during which the hedged transactions are recognized in earnings. The effective portion of changes in the fair value of derivatives designated that qualify as cash flow hedges is recorded in AOCL, net of taxes, and is subsequently reclassified into earnings in the period that the hedged forecasted transaction affects earnings. The ineffective portion of the change in fair value of the derivatives is recognized directly in earnings. Amounts reported in AOCL related to derivatives will be reclassified to interest expense as interest payments are made on the Company’s variable-rate debt. For the year ended March 31, 2019, the Company performed both retrospective and prospective hedge effectiveness analyses for the interest rate swaps designated as cash flow hedges. The Company applied the long-haul method outlined in ASC Topic 815, Derivatives and Hedging, to assess retrospective and prospective effectiveness of the interest rate swaps. A quantitative effectiveness analysis assessment of the hedging relationship was performed using regression analysis. As of March 31, 2019, the Company has determined that the hedging relationship was highly effective. The pre-tax impact of loss on derivatives designated for hedge accounting recognized in other comprehensive income (loss) was $31 million ($23 million, net of tax) during the fiscal year ended March 31, 2019. As of March 31, 2019, we expect amounts of approximately $6 million pertaining to cash flow hedges to be reclassified from accumulated other comprehensive income into earnings over the next 12 months. Fair Value of Derivative Instruments All derivatives are recorded at fair value. The Company’s accounting treatment for these derivative instruments is based on its hedge designation. As of March 31, 2019, the gross fair value of our derivative liabilities in interest rate swaps designated for hedge accounting is $26 million, of which $4 million is presented in other current liabilities and $22 million is presented in other liabilities on the balance sheet. The fair value of interest rate swaps is estimated based on valuation models that use interest rate yield curves as Level 2 inputs. Other risks The Company is exposed to the risk of losses in the event of non-performance by counter parties to its derivative contracts. To mitigate counter party credit risk, the Company regularly reviews its credit exposure and the creditworthiness of counter parties. The Company also enters into enforceable master netting arrangements with some of its counter parties. However, for financial reporting purposes, it is Company policy not to offset derivative assets and liabilities despite the existence of enforceable master netting arrangements with some of its counter parties.

Derivative Instruments

In the normal course of business, the Company is exposed to interest rate fluctuations. As part of its risk management strategy, the Company uses derivative instruments, primarily interest rate swaps, to hedge certain interest rate exposures. The Company’s objective is to add stability to interest expense and to manage its exposure to movements in market interest rates. The Company does not use derivative instruments for trading or any speculative purpose.

Derivatives Designated for Hedge Accounting

The Company uses interest rate swap agreements designated as cash flow hedges to mitigate its exposure to interest rate risk associated with the variability of cash outflows for interest payments on certain floating interest rate debt, which effectively converted the debt into fixed interest rate debt. The Company entered into $1.4 billion of notional interest rate swap agreements concurrently with its Credit Facilities (as defined under Note 12 – “Debt”), on May 31, 2018, and $200 million of notional interest rate swap agreements in October 2018. As of March 31, 2019, the Company had interest rate swap agreements with a total notional amount of $1.6 billion. The Company initially accounted for all changes in fair value of its interest rate swaps on the statements of operations until designation as a cash flow hedge of interest rate risk on June 22, 2018. As a result, the Company recorded a gain of $5 million in the first quarter, included in interest expense, net on the statement of operations for the fiscal year ended March 31, 2019.

Following the June 22, 2018 cash flow hedge designation, all changes in the hedging instruments’ fair value are recorded in accumulated other comprehensive loss (“AOCL”) and subsequently reclassified into earnings in the period during which the hedged transactions are recognized in earnings. The effective portion of changes in the fair value of derivatives designated that qualify as cash flow hedges is recorded in AOCL, net of taxes, and is subsequently reclassified into earnings in the period that the hedged forecasted transaction affects earnings. The ineffective portion of the change in fair value of the derivatives is recognized directly in earnings. Amounts reported in AOCL related to derivatives will be reclassified to interest expense as interest payments are made on the Company’s variable-rate debt.

For the year ended March 31, 2019, the Company performed both retrospective and prospective hedge effectiveness analyses for the interest rate swaps designated as cash flow hedges. The Company applied the long-haul method outlined in ASC Topic 815, Derivatives and Hedging, to assess retrospective and prospective effectiveness of the interest rate swaps. A quantitative effectiveness analysis assessment of the hedging relationship was performed using regression analysis. As of March 31, 2019, the Company has determined that the hedging relationship was highly effective.

The pre-tax impact of loss on derivatives designated for hedge accounting recognized in other comprehensive income (loss) was $31 million ($23 million, net of tax) during the fiscal year ended March 31, 2019. As of March 31, 2019, we expect amounts of approximately $6 million pertaining to cash flow hedges to be reclassified from accumulated other comprehensive income into earnings over the next 12 months.

Fair Value of Derivative Instruments

All derivatives are recorded at fair value. The Company’s accounting treatment for these derivative instruments is based on its hedge designation. As of March 31, 2019, the gross fair value of our derivative liabilities in interest rate swaps designated for hedge accounting is $26 million, of which $4 million is presented in other current liabilities and $22 million is presented in other liabilities on the balance sheet. The fair value of interest rate swaps is estimated based on valuation models that use interest rate yield curves as Level 2 inputs.

Other risks

The Company is exposed to the risk of losses in the event of non-performance by counter parties to its derivative contracts. To mitigate counter party credit risk, the Company regularly reviews its credit exposure and the creditworthiness of counter parties. The Company also enters into enforceable master netting arrangements with some of its counter parties. However, for financial reporting purposes, it is Company policy not to offset derivative assets and liabilities despite the existence of enforceable master netting arrangements with some of its counter parties.