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Shareholders' Equity (Schedule Of Net Income Per Common Share) (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Earnings Per Share [Line Items] |  |  |  |  |  |
Net income (loss) to common shareholders |  | $ 2,711,022 |  | $ 1,960,060 | $ (252,277) |
Adjustment of redeemable noncontrolling interests |  | (111,700) |  | 6,212 | (69,896) |
Adjusted net income (loss) to common shareholders |  | $ 2,599,322 |  | $ 1,966,272 | $ (322,173) |
Basic common shares outstanding |  | 13,017,000 |  | 13,347,000 | 13,580,000 |
Diluted common shares outstanding |  | 13,041,000 |  | 13,378,000 | 13,580,000 |
Basic net income (loss) per common share |  | $ 199.69 |  | $ 147.32 | $ (23.72) |
Diluted net income per common share |  | $ 199.32 |  | $ 146.98 | $ (23.72) | [1]
Number of shares available for future awards | [2] | 284,049 |  |  |  |
Restricted Stock Units (RSUs) [Member] |  |  |  |  |  |
Earnings Per Share [Line Items] |  |  |  |  |  |
Dilutive potential common shares from restricted stock units and restricted stock |  | 24,000 | [2] | 31,000 | 0 | [1]
Potential incremental common shares attributable to share-based payment arrangements | [1] |  |  |  | 33,000 |
[1] | The impact of 33 thousand shares from restricted stock units and restricted stock was excluded from the computation of diluted net loss per common share for the year ended December 31, 2022 because the effect would have been anti-dilutive.
[2] | The Company has issued grants and awards of restricted stock units to employees as performance, retention or hiring incentives, as well as awards of restricted stock to non-employee directors, under its equity incentive compensation plan. At December 31, 2024, there were 284,049 shares available for future awards under the Company's equity incentive compensation plan.

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