Fair Value Measurements (Tables)

9 Months Ended

Apr. 30, 2018

Fair Value Measurements [Abstract]

Summary of balance of assets measured at fair value on a recurring basis

	Level 1 (1)		Level 2 (2)		Level 3 (3)		Total
	(in thousands)
April 30, 2018
Available-for-sale securities:
Marketable securities	$	1,794	$	8,776	$	—	$	10,570
July 31, 2017
Available-for-sale securities:
Marketable securities	$	12,151	$	46,121	$	—	$	58,272
Rafael Pharma Series D Note		—		—		6,300		6,300
Total	$	12,151	$	46,121	$	6,300	$	64,572

(1) – quoted prices in active markets for identical assets or liabilities

(2) – observable inputs other than quoted prices in active markets for identical assets and liabilities

(3) – no observable pricing inputs in the market

Summary of assets measured at fair value on a recurring basis using significant unobservable inputs (Level 3)

	Three Months Ended April 30,					Nine Months Ended April 30,
	2018			2017		2018			2017
	(in thousands)
Balance, beginning of period	$	6,300		$	4,200	$	6,300		$	2,000
Purchases		—			—		—			2,200
Rafael Spin-Off		(6,300	)		—		(6,300	)		—
Balance, end of period	$	—		$	4,200	$	—		$	4,200
Change in unrealized gains or losses for the period included in earnings for assets held at the end of the period	$	—		$	—	$	—		$	—