Borrowings - Summary of Long-Term Debt, Net of Debt Issuance Costs (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument
Senior Notes	$ 249		$ 248
Trust Preferred Securities	$ 247	$ 247
Interest Rate	6.125%		6.125%
Total other long-term debt	$ 496	$ 495	$ 495
Plus 3.25%, matures 2032
Debt Instrument
Trust Preferred Securities	$ 26		$ 26
Interest Rate	5.20%		6.07%
Plus 3.25%, matures 2033
Debt Instrument
Trust Preferred Securities	$ 26		$ 26
Interest Rate	5.24%		5.69%
Plus 3.25%, matures 2033
Debt Instrument
Trust Preferred Securities	$ 26		$ 26
Interest Rate	5.21%		6.05%
Plus 2.00%, matures 2035
Debt Instrument
Trust Preferred Securities	$ 26		$ 26
Interest Rate	3.99%		4.44%
Plus 2.00%, matures 2035
Debt Instrument
Trust Preferred Securities	$ 26		$ 26
Interest Rate	3.99%		4.44%
Plus 1.75%, matures 2035
Debt Instrument
Trust Preferred Securities	$ 51		$ 51
Interest Rate	3.64%		4.54%
Plus 1.50%, matures 2035
Debt Instrument
Trust Preferred Securities	$ 25		$ 25
Interest Rate	3.49%		3.94%
Plus 1.45%, matures 2037
Debt Instrument
Trust Preferred Securities	$ 25		$ 25
Interest Rate	3.34%		4.24%
Plus 2.50%, matures 2037
Debt Instrument
Trust Preferred Securities	$ 16		$ 16
Interest Rate	4.39%		5.29%

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

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