Derivative Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2018

Derivative Financial Instruments

Schedule of fair value of derivative financial instruments, excluding derivative financial instruments held in certain consolidated sponsored funds

			December 31,		December 31,
			2018		2017
	Balance sheet
	location	Fair value		Fair value
		(in thousands)
Total return swap contracts	Prepaid expenses and other current assets	$	4,968		—
Total return swap contracts	Other current liabilities		—		1,093
Total		$	4,968		1,093

Schedule of net gains (losses) recognized in income of derivative financial instrument

		Year ended
	Income statement	December 31,
	location		2018	2017
		(in thousands)
Total return swap contracts	Investment and other income (loss)	$	15,163	(36,368)