Fair Value Measures (Tables)

6 Months Ended

Mar. 31, 2019

Fair Value Disclosures [Abstract]

Assets and Liabilities Measured at Fair Value on Recurring Basis

Assets and liabilities measured at fair value on a recurring basis at March 31, 2019 and September 30, 2018 consisted of the following (dollars in thousands):

	March 31, 2019
	Level 1		Level 2			Level 3			Total
Assets:
Money market funds(a)	$	380,124	$	—		$	—		$	380,124
Time deposits(b)	—		97,225			—			97,225
Commercial paper, $37,852 at cost(b)	—		38,061			—			38,061
Corporate notes and bonds, $46,694 at cost(b)	—		46,686			—			46,686
Foreign currency exchange contracts(b)	—		689			—			689
Total assets at fair value	$	380,124	$	182,661		$	—		$	562,785
Liabilities:
Foreign currency exchange contracts(b)	$	—	$	(350	)	$	—		$	(350	)
Contingent acquisition payments(c)	—		—			(1,450		)	(1,450		)
Total liabilities at fair value	$	—	$	(350	)	$	(1,450	)	$	(1,800	)

	September 30, 2018
	Level 1		Level 2			Level 3			Total
Assets:
Money market funds(a)	$	200,004	$	—		$	—		$	200,004
Time deposits(b)	—		88,158			—			88,158
Commercial paper, $27,194 at cost(b)	—		27,363			—			27,363
Corporate notes and bonds, $57,563 at cost(b)	—		57,417			—			57,417
Foreign currency exchange contracts(b)	—		143			—			143
Total assets at fair value	$	200,004	$	173,081		$	—		$	373,085
Liabilities:
Foreign currency exchange contracts(b)	$	—	$	(1,192	)	$	—		$	(1,192	)
Contingent acquisition payments(c)	—		—			(4,000		)	(4,000		)
Total liabilities at fair value	$	—	$	(1,192	)	$	(4,000	)	$	(5,192	)

Changes in Fair Value of Contingent Earn-Out Liabilities

The following table provides a summary of changes in the aggregate fair value of the contingent acquisition payments for all periods presented (dollars in thousands):

	Three Months Ended March 31,						Six Months Ended March 31,
	2019			2018			2019			2018
Balance at beginning of period	$	3,979		$	10,431		$	4,000		$	8,648
Earn-out liabilities established at time of acquisition	—			—			—			500
Payments and foreign currency translation	(2,529		)	(79		)	(2,550		)	(96		)
Adjustments to fair value included in acquisition-related costs, net	—			1,400			—			2,700
Balance at end of period	$	1,450		$	11,752		$	1,450		$	11,752