Fair Value of Financial Instruments (Unaudited) Long-term Debt (Details 3) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Mar. 01, 2021	Dec. 31, 2020
Debt Instruments [Abstract]
2021 Note, Face Amount		$ 700
2021 Note, Interest Rate, Stated Percentage		3.50%
2022 Note, Face Amount		$ 1,500
2022 Note, Interest Rate, Stated Percentage		2.55%
Long-term Debt, Fair Value	$ 15,200		$ 18,200
Redemption Premium	$ 54