Financial Instruments and Fair Value Measurement (Tables)

3 Months Ended

Dec. 31, 2017

Financial Instruments and Fair Value Measurement

Summary of available-for-sale securities

			Gross		Gross		Estimated
			Unrealized		Unrealized		Fair
	Cost		Gains		Losses		Value
	(in thousands)
Equity Securities:
December 31, 2017	$	38,473	$	30,856	$	—	$	69,329
September 30, 2017	$	38,473	$	31,700	$	—	$	70,173

Summary of assets and liabilities measured at fair value

The following table summarizes our assets and liabilities measured at fair value presented in our Consolidated Condensed Balance Sheet as of December 31, 2017:

	Fair Value		(Level 1)		(Level 2)		(Level 3)
	(in thousands)
Recurring fair value measurements:
Short-term investments:
Corporate and municipal debt securities	$	15,716	$	—	$	15,716	$	—
U.S. government and federal agency securities		26,825		26,825		—		—
Total short-term investments		42,541		26,825		15,716		—
Cash and cash equivalents		383,664		383,664		—		—
Investments		69,329		69,329		—		—
Other current assets		38,226		38,226		—		—
Other assets		6,798		6,798		—		—
Total assets measured at fair value	$	540,558	$	524,842	$	15,716	$	—
Liabilities:
Contingent earnout liability	$	17,356	$	—	$	—	$	17,356

Summary of supplemental fair value information about long-term fixed-rate debt

	December 31,		September 30,
	2017		2017
	(in millions)
Carrying value of long-term fixed-rate debt	$	493.2	$	492.9
Fair value of long-term fixed-rate debt	$	527.8	$	529.0