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Shareholders' Equity (Schedule Of Net Income (Loss) Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Line Items]
Net income to common shareholders	$ 1,025,184	$ 488,652
Adjustment of redeemable noncontrolling interests	(32,602)	13,473
Adjusted net income to common shareholders	$ 992,582	$ 502,125
Basic common shares outstanding	13,137	13,450
Diluted common shares outstanding	13,159	13,475
Earnings Per Share, Basic	$ 75.56	$ 37.33
Earnings Per Share, Diluted	$ 75.43	$ 37.26
Restricted Stock Units (RSUs) [Member]
Earnings Per Share [Line Items]
Dilutive potential common shares from restricted stock units and restricted stock	22	25

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