Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2019

Fair Value Disclosures [Abstract]

Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

The following tables summarize the Company's financial liabilities measured at fair value on a recurring basis as of September 30, 2019 and December 31, 2018 (in thousands):

	Carrying Amount as of September 30, 2019		Fair Value Measurements As of September 30, 2019
			Level 1		Level 2		Level 3
3.25% convertible senior notes due 2020	$	—	$	—	$	—	$	—
3.25% convertible senior notes due 2023*	48,635		—		—		48,635
Preferred stock	4,894		—		—		4,894

* The amount presented excludes accrued, but unpaid, payment-in-kind interest of $0.1 million as of September 30, 2019.

	Carrying Amount as of December 31, 2018		Fair Value Measurements As of December 31, 2018
			Level 1		Level 2		Level 3
3.25% convertible senior notes due 2020	$	27,974	$	—	$	—	$	27,974

Reconciliation of Beginning and Ending Balances of Assets Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs (Level 3)

The following tables provide a reconciliation of the beginning and ending balances of liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) (in thousands):

3.25% convertible senior notes due 2020	2019
Balance at January 1, 2019	$	27,974
Change in fair value	2,529
Extinguishment of convertible senior notes ($29.6 million face value)	(30,503		)
Balance at September 30, 2019	$	—

3.25% convertible senior notes due 2023	2019
Balance at January 1, 2019	$	—
New issuance ($29.6 million face value)	37,916
New issuance ($8.0 million face value)	10,254
Change in fair value	465
Balance at September 30, 2019	$	48,635