Fair Value Measurements (Tables)

3 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of assets measured at fair value on a recurring basis

The assets measured at fair value on a recurring basis were as follows: 

(in millions)	Level 1		Level 2		Level 3		NAV as a Practical Expedient		Total
as of December 31, 2019
Assets
Equity securities, at fair value
Sponsored funds	$	794.9	$	10.6	$	—	$	69.2	$	874.7
Other equity securities	24.2		0.5		10.9		26.1		61.7
Debt securities
Trading	—		29.6		17.9		—		47.5
Available-for-sale	—		2.0		—		—		2.0
Life settlement contracts	—		—		11.4		—		11.4
Total Assets Measured at Fair Value	$	819.1	$	42.7	$	40.2	$	95.3	$	997.3

(in millions)	Level 1		Level 2		Level 3		NAV as a Practical Expedient		Total
as of September 30, 2019
Assets
Equity securities, at fair value
Sponsored funds	$	397.0	$	—	$	—	$	69.4	$	466.4
Other equity securities	22.6		3.2		0.8		37.0		63.6
Debt securities
Trading	—		24.4		19.8		—		44.2
Available-for-sale	—		4.0		—		—		4.0
Life settlement contracts	—		—		11.5		—		11.5
Total Assets Measured at Fair Value	$	419.6	$	31.6	$	32.1	$	106.4	$	589.7

Schedule of changes in Level 3 assets and liability

Changes in the Level 3 assets and liability were as follows: 

	2019			2018
(in millions)	Investments			Investments			Contingent Consideration Liability
for the three months ended December 31,
Balance at beginning of period	$	32.1		$	32.6		$	(38.7	)
Total realized and unrealized gains (losses)
Included in investment and other income (losses), net	(0.3		)	2.8			—
Included in general, administrative and other expense	—			—			(1.3		)
Purchases	12.6			—			—
Sales	(1.5		)	(4.3		)	—
Settlements	(2.7		)	—			—
Transfers out of Level 3	—			(2.1		)	—
Balance at End of Period	$	40.2		$	29.0		$	(40.0	)
Change in unrealized gains (losses) included in net income relating to assets and liability held at end of period	$	(0.3	)	$	2.8		$	(1.3	)

Schedule of valuation techniques and significant unobservable inputs used in level 3 fair value measurements

Valuation techniques and significant unobservable inputs used in the Level 3 fair value measurements were as follows:

(in millions)
as of December 31, 2019	Fair Value		Valuation Technique	Significant Unobservable Inputs	Range (Weighted Average1)
Equity securities, at fair value	$	10.9	Market pricing	Private sale pricing	$1,000 per share
Debt securities, trading	17.9		Discounted cash flow	Discount rate	1.5%–15.5% (6.8%)
				Risk premium	2.0%–6.1% (3.8%)
Life settlement contracts	11.4		Discounted cash flow	Life expectancy	19–105 months (55)
				Discount rate	10.0%–20.0% (13.4%)

(in millions)
as of September 30, 2019	Fair Value		Valuation Technique	Significant Unobservable Inputs	Range (Weighted Average1)
Debt securities, trading	$	19.8	Discounted cash flow	Discount rate	2.7%–13.3% (6.7%)
				Risk premium	2.0%–6.1% (4.2%)
Life settlement contracts	11.5		Discounted cash flow	Life expectancy	19–107 months (57)
				Discount rate	8.0%–20.0% (13.2%)

Schedule of financial instruments not measured at fair value

Financial instruments that were not measured at fair value were as follows:

(in millions)	Fair Value Level	December 31, 2019				September 30, 2019
		Carrying Value		Estimated Fair Value		Carrying Value		Estimated Fair Value
Financial Assets
Cash and cash equivalents	1	$	5,817.3	$	5,817.3	$	5,803.4	$	5,803.4
Other investments
Time deposits	2	16.8		16.8		15.4		15.4
Equity securities	3	18.9		20.7		17.3		19.2
Financial Liability
Debt	2	$	697.0	$	720.2	$	696.9	$	718.7