Fair Value Measurements (Tables)

3 Months Ended

Jun. 30, 2018

Fair Value, Assets, Liabilities and Stockholders' Equity Measured on Recurring Basis [Abstract]

Schedule of fair value, assets and liabilities measured on recurring basis

Assets measured at fair value on a recurring basis at June 30, 2018 are as follows (in millions):

	Quoted Prices in Active Markets for Identical Instruments (Level 1)		Significant Other Observable Inputs (Level 2)		Total Balance
Assets
Cash and cash equivalents:
Money market mutual funds	$	46.4	$	—	$	46.4
Deposit accounts	—		588.8		588.8
Short-term investments:
Marketable equity securities	3.2		—		3.2
Time deposits	—		11.3		11.3
Total assets measured at fair value	$	49.6	$	600.1	$	649.7

Assets measured at fair value on a recurring basis at March 31, 2018 are as follows (in millions):

	Quoted Prices in Active Markets for  Identical Instruments (Level 1)		Significant Other Observable Inputs (Level 2)		Total Balance
Assets
Cash and cash equivalents:
Money market mutual funds	$	121.0	$	—	$	121.0
Deposit accounts	—		641.6		641.6
Commercial Paper	—		118.7		118.7
Government agency bonds	—		20.0		20.0
Short-term investments:
Marketable equity securities	2.8		—		2.8
Corporate bonds and debt	—		542.9		542.9
Time deposits	—		11.5		11.5
Government agency bonds	—		723.2		723.2
Municipal bonds - taxable	—		14.9		14.9
Total assets measured at fair value	$	123.8	$	2,072.8	$	2,196.6