Fixed Assets (Summary Of Fixed Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Abstract]
Office equipment	$ 354,292	$ 323,841
Leasehold improvements	113,576	105,187
Building	65,327	62,803
Fixed assets, gross	533,195	491,831
Accumulated depreciation and amortization	364,989	(323,916)
Fixed assets, net	$ 168,206	$ 167,915

Accumulated depreciation depletion and amortization fixed assets excluding leased assets.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Fixed assets gross excluding leased assets.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Fixed assets net excluding leased assets.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=124098289&loc=d3e6812-107765

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

+ Details

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Balance Type:	debit
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- Definition

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

+ References

+ Details

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Balance Type:	debit
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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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

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