Long Term Debt and Other Borrowings - Interest Cost Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019
Debt Instrument [Line Items]
Long-term debt	$ 4,512,349
Senior notes
Debt Instrument [Line Items]
Long-term debt	$ 2,500,000	$ 2,500,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant