Description of Business and Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2018

Accounting Policies [Abstract]

Summary of Cash and Cash Equivalents, Measured at Fair Value on a Recurring Basis

The following table summarizes, by major security type, our cash, cash equivalents and short-term investments that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy (in thousands):

	December 31, 2018									December 31, 2017
	Cost or Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Total Estimated Fair Value		Total Estimated Fair Value
Cash	$	919	$	—	$	—		$	919	$	43,218
Level 1 securities:
Money market funds	20,525		—		—			20,525		—
Level 2 securities:
U.S. government and agency securities	15,217		1		(5		)	15,213		—
Corporate debt securities	30,393		1		(13		)	30,381		—
	$	67,054	$	2	$	(18	)	$	67,038	$	43,218
Less: restricted cash								—		(16,000		)
Total cash, cash equivalents and short-term investments								$	67,038	$	27,218

Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash

The following table provides reconciliations of cash, cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total of the same such amounts shown in the consolidated statements of cash flows.

	December 31, 2018		December 31, 2017
Cash and cash equivalents	$	36,439	$	27,218
Restricted cash	—		16,000
Total cash, cash equivalents and restricted cash shown in the consolidated statements of cash flows	$	36,439	$	43,218