Fixed Assets (Summary Of Fixed Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Office equipment	$ 213,083	$ 356,707
Internally developed software	103,351	85,993
Leasehold improvements	89,382	141,585
Building	81,207	80,771
Aircraft engine operating leases	4,886	2,370
Fixed assets, gross	491,909	667,426
Accumulated depreciation and amortization	(298,753)	(475,898)
Fixed assets, net	$ 193,156	$ 191,528

Accumulated depreciation depletion and amortization fixed assets excluding leased assets.

No definition available.

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- Definition

Fixed assets gross excluding leased assets.

+ References

No definition available.

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- Definition

Fixed assets net excluding leased assets.

+ References

No definition available.

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- Definition

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 30
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- Definition

Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

+ References

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- Definition

Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

+ References

+ Details

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- References

No definition available.

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- Definition

Amount, before accumulated depreciation, of lessor's underlying asset for which right to use has been conveyed to lessee under operating lease.

+ References

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