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Restricted Stock and Performance Share Awards - Performance Share Award Activity under the LTIP (Details) - Performance Shares - Long Term Incentive Plan - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Provisional performance share awards approved (in shares)	0.1	0.1
Aggregate approval-date fair value	$ 24	$ 22
Compensation expense recognized	3	6
Intrinsic value of unvested restricted stock units (end of period)	73	113
Distributions	$ 24	$ 36

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