Face (par) amount of debt instrument at time of issuance.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

+ References

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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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.

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Related Party Debt (Details) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
Related Party Debt (Details) - USD ($)	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Apr. 01, 2015
Related Party Transaction [Line Items]
Related party debt outstanding	$ 0		$ 0		$ 597,150,000	$ 1,747,363,000
Subordinated Debt \| Subordinated Demand Promissory Notes \| Affiliated Entity
Related Party Transaction [Line Items]
Debt instrument, face amount								$ 1,800,000,000
Related party debt outstanding					478,500,000	1,700,000,000
Accrued interest					$ 118,700,000	$ 91,300,000
Interest rate					2.72%	2.12%
Interest expense	$ 1,000,000.0	$ 10,100,000	$ 4,100,000	$ 20,800,000	$ 27,400,000	$ 35,200,000	$ 25,600,000