Investments - Schedule of Available-for-sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Investment [Line Items]
Amortized Cost	$ 58,595	$ 11,851
Gross Unrealized Gains	7	1
Gross Unrealized Losses	(83)	(13)
Fair Value	58,519	11,839
Certificates of deposit
Investment [Line Items]
Amortized Cost	7,257
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair Value	7,257
US Treasury securities
Investment [Line Items]
Amortized Cost	8,553
Gross Unrealized Gains	1
Gross Unrealized Losses	(10)
Fair Value	8,544
US Agency securities
Investment [Line Items]
Amortized Cost	4,514
Gross Unrealized Gains	0
Gross Unrealized Losses	(13)
Fair Value	4,501
Asset-backed securities
Investment [Line Items]
Amortized Cost	5,554	2,510
Gross Unrealized Gains	3	0
Gross Unrealized Losses	0	(3)
Fair Value	5,557	2,507
Corporate notes and bonds
Investment [Line Items]
Amortized Cost	32,717	9,341
Gross Unrealized Gains	3	1
Gross Unrealized Losses	(60)	(10)
Fair Value	$ 32,660	$ 9,332

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

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