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Stock Incentive Plan (Schedule of Share-based Compensation, Unearned Compensation Related to RSU's) (Details) - Restricted Stock Units (RSUs) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Changes In Unearned Compensation [Roll Forward] |  |  |
Unearned compensation at beginning of year | $ 135,535 | $ 132,310 | $ 128,390
RSUs granted, net of cancellations | 60,628 | 56,711 | 54,270
RSUs expensed | 47,611 | (46,441) | (47,108)
RSUs forfeitures | 6,492 | (7,045) | (3,242)
Unearned compensation at end of year | $ 142,060 | $ 135,535 | $ 132,310

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- Details
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