Fair Value Measurements (Fair Values of Financial Instruments Measured On Recurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment in Consensus	$ 238,151	$ 229,200
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment in Consensus	238,151	229,200
Total assets measured at fair value	276,634	373,455
Contingent consideration	10,087	5,775
Debt	1,186,652	1,345,311
Total liabilities measured at fair value	1,196,739	1,351,086
Fair Value \| Money market and other funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market and other funds	38,483	144,255
Fair Value \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment in Consensus	238,151	229,200
Total assets measured at fair value	276,634	373,455
Contingent consideration	0	0
Debt	1,186,652	1,345,311
Total liabilities measured at fair value	1,186,652	1,345,311
Fair Value \| Level 1 \| Money market and other funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market and other funds	38,483	144,255
Fair Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment in Consensus	0	0
Total assets measured at fair value	0	0
Contingent consideration	0	0
Total liabilities measured at fair value	0	0
Fair Value \| Level 2 \| Money market and other funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market and other funds	0	0
Fair Value \| Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment in Consensus	0	0
Total assets measured at fair value	0	0
Contingent consideration	10,087	5,775
Debt	0	0
Total liabilities measured at fair value	10,087	5,775
Fair Value \| Level 3 \| Money market and other funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market and other funds	0	0
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment in Consensus	238,151	229,200
Total assets measured at fair value	276,634	373,455
Contingent consideration	10,087	5,775
Total liabilities measured at fair value	1,133,032	1,096,402
Carrying Value \| Money market and other funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Money market and other funds	$ 38,483	$ 144,255

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=116859824&loc=d3e6819-128478

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-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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