Long Term Debt and Other Borrowings - Revolving Credit Facility Narrative (Details) - Revolving credit facility - USD ($)	Feb. 25, 2019	Jun. 30, 2019
Line of Credit Facility [Line Items]
Revolving unsecured credit facility	$ 1,250,000,000
Additional increase in the facility, available expansion	600,000,000.0
Revolving unsecured credit facility, available expansion	$ 1,850,000,000
Commercial paper		$ 0
Federal Funds rate
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (percent)	0.50%
One-month LIBOR
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (percent)	1.00%
One-month LIBOR | Minimum
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (percent)	0.00%
One-month LIBOR | Maximum
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (percent)	0.50%
London Interbank Offered Rate (LIBOR) | Minimum
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (percent)	0.90%
London Interbank Offered Rate (LIBOR) | Maximum
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate (percent)	1.50%