Fair value measurements	9 Months Ended
Fair value measurements	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair value measurements	Fair value measurements The Company records certain assets and liabilities at fair value. Fair value is defined as the price that would be received to sell an asset, or paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants at the measurement date. A three-level fair value hierarchy that prioritizes the inputs used to measure fair value is described below. This hierarchy requires entities to maximize the use of observable inputs and minimize the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows: •Level 1 — Quoted prices in active markets for identical assets or liabilities. •Level 2 — Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets; quoted prices for identical or similar assets and liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data. •Level 3 — Unobservable inputs that are supported by little or no market activity. This includes certain pricing models, discounted cash flow methodologies, and similar techniques that use significant unobservable inputs. The carrying amounts of financial instruments, including cash and cash equivalents, accounts receivable, unbilled services, contract assets, accounts payable, and unearned revenue approximate fair value due to the short maturities of these instruments. Recurring Fair Value Measurements The Company classifies its interests in investments in equity-long term having considered the nature of its investment, the extent of influence over operating and financial decisions and the availability of readily determinable fair values. The Company determined that the interests in funds at September 30, 2021 and December 31, 2020 meet the definition of equity securities without readily determinable fair values. The Company concluded that the interests held at September 30, 2021 and December 31, 2020 qualify for the Net Asset Value (NAV) practical expedient in ASC 820 'Fair value measurements and disclosures'. Any increases or decreases in fair value are recognized in net income in the period. These are therefore measured at Level 3 of the fair value hierarchy. The value of these investments were $22.8 million at September 30, 2021 and $15.8 million at December 31, 2020. Non-recurring Fair Value Measurements Certain assets and liabilities are carried on the accompanying Condensed Consolidated Balance Sheet at cost and are not re-measured to fair value on a recurring basis. These assets include finite-lived intangible assets that are tested for impairment when a triggering event occurs and goodwill and identifiable indefinite-lived intangible assets that are tested for impairment annually or when a triggering event occurs. As of September 30, 2021, assets carried on the balance sheet and not re-measured to fair value on a recurring basis totaled approximately $13,750.4 million and are identified as Level 3 assets. These assets are comprised of goodwill of $8,935.2 million and identifiable intangible assets, net of $4,815.2 million. Refer to "Note 12 - Non-current bank credit lines and loan facilities" for additional information regarding the fair value of long-term debt balances.

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.