Long-Term Debt and Shareholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Debt And Equity [Abstract]
Shares outstanding (in shares)	147.7
Common stock, par value (in dollars per share)	$ 0.001		$ 0.001
Common stock and additional paid-in capital change	$ (26)
Common stock and additional paid-in capital percentage change	2.00%
Common stock and additional paid-in capital	$ 1,700
Common stock repurchased (in shares)	0.9
Common stock repurchased	$ 35	$ 50
Common stock repurchased (in dollars per share)	$ 39.32
Transfer in accumulated unrecognized loss	$ 2,000
Unrealized loss, after tax	$ 1,500