Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Summary of Placement in the Fair Value Hierarchy of Financial Assets that are Measured at Fair Value on a Recurring Basis

The following table presents the placement in the fair value hierarchy of financial assets that are measured at fair value on a recurring basis, including the items for which the fair value option has been elected, at June 30, 2017:

	Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		June 30, 2017
Assets
U.S. government debt securities	$	—	$	91,987	$	—	$	91,987
Equity securities	18,042		5,859		—		23,901
Preferred stock	—		—		144,742		144,742
Other	—		9,129		—		9,129
Total	$	18,042	$	106,975	$	144,742	$	269,759

The following table presents the placement in the fair value hierarchy of financial assets that are measured at fair value on a recurring basis, including the items for which the fair value option has been elected, at December 31, 2016:

	Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		December 31, 2016
Assets
U.S. government debt securities	$	—	$	180,323	$	—	$	180,323
Equity securities	15,544		7,978		—		23,522
Preferred stock	—		—		129,545		129,545
Other	—		1,917		—		1,917
Total	$	15,544	$	190,218	$	129,545	$	335,307

Schedule of Changes in Level 3 Liabilities

The changes in the fair value of the Level 3 liabilities during the six months ended June 30, 2017 were as follows:

	Six Months Ended   June 30, 2017
Beginning balance	$	2,081
Acquisition date fair value of contingent consideration liability (Note 3)	585
Change in fair value of contingent consideration recognized in selling, general and administrative expenses	160
Ending balance	$	2,826