Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Transactions - Narrative (Details) - USD ($) $ in Thousands, shares in Millions			3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 01, 2022	Oct. 01, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Business Acquisition [Line Items]
Cash					$ 245,021	$ 1,889
Provision for (benefit from) income taxes			$ (45,516)	$ 234	$ (44,498)	$ 936
Customer relationships
Business Acquisition [Line Items]
Weighted- Average Remaining Useful Life					16 years		14 years 10 months 24 days
Technology
Business Acquisition [Line Items]
Weighted- Average Remaining Useful Life					2 years 10 months 24 days		2 years
Corporate trade name
Business Acquisition [Line Items]
Weighted- Average Remaining Useful Life					13 years		12 years 4 months 24 days
IPG
Business Acquisition [Line Items]
Voting interests acquired	100.00%
Total consideration	$ 461,663
Cash	$ 256,488
Equity interest issued or issuable, number of shares (in shares)	3.7
Fair value of Class A common stock issued	$ 130,175
Contingent consideration arrangements (up to)	87,000
Fair value of contingent consideration	75,000
Goodwill, expected tax deductible amount	$ 0
Provision for (benefit from) income taxes			$ 46,800		$ 46,800
IPG \| Customer relationships
Business Acquisition [Line Items]
Weighted- Average Remaining Useful Life	20 years
IPG \| Technology
Business Acquisition [Line Items]
Weighted- Average Remaining Useful Life	5 years
IPG \| Corporate trade name
Business Acquisition [Line Items]
Weighted- Average Remaining Useful Life	15 years
Vital Decisions
Business Acquisition [Line Items]
Voting interests acquired		100.00%
Total consideration		$ 117,726
Cash		$ 46,500
Equity interest issued or issuable, number of shares (in shares)		1.8
Fair value of Class A common stock issued		$ 56,626
Contingent consideration arrangements (up to)		45,000
Fair value of contingent consideration		14,600
Goodwill, expected tax deductible amount		$ 69,600
Vital Decisions \| Customer relationships
Business Acquisition [Line Items]
Weighted- Average Remaining Useful Life		13 years
Vital Decisions \| Technology
Business Acquisition [Line Items]
Weighted- Average Remaining Useful Life		5 years
Vital Decisions \| Corporate trade name
Business Acquisition [Line Items]
Weighted- Average Remaining Useful Life		15 years