v3.6.0.2

Fair Value Measurements - Hierarchy (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015
Transfers between Levels 1 and 2 |  |
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount | $ 0 | $ 0
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount | 0 | 0
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount | 0 | 0
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount | 0 | 0
Transfers into and out of Level 3 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 | 0 | 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 | 0 | 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3 | 0 | 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3 | 0 | 0
Recurring |  |
Financial Assets: |  |
Total financial assets | 141,637,000 | 207,552,000
Current Liabilities: |  |
Warrants | 3,792,000 | 3,649,000
Total financial liabilities | 3,792,000 | 3,649,000
Recurring | Money market deposits |  |
Financial Assets: |  |
Total financial assets | 10,777,000 | 5,966,000
Recurring | U.S. Treasury securities |  |
Financial Assets: |  |
Total financial assets | 57,442,000 | 103,813,000
Recurring | U.S. agency securities |  |
Financial Assets: |  |
Total financial assets | 56,114,000 | 78,853,000
Recurring | Municipal securities |  |
Financial Assets: |  |
Total financial assets | 17,304,000 | 18,920,000
Recurring | Level 1 |  |
Financial Assets: |  |
Total financial assets | 68,219,000 | 109,779,000
Recurring | Level 1 | Money market deposits |  |
Financial Assets: |  |
Total financial assets | 10,777,000 | 5,966,000
Recurring | Level 1 | U.S. Treasury securities |  |
Financial Assets: |  |
Total financial assets | 57,442,000 | 103,813,000
Recurring | Level 2 |  |
Financial Assets: |  |
Total financial assets | 73,418,000 | 97,773,000
Recurring | Level 2 | U.S. agency securities |  |
Financial Assets: |  |
Total financial assets | 56,114,000 | 78,853,000
Recurring | Level 2 | Municipal securities |  |
Financial Assets: |  |
Total financial assets | 17,304,000 | 18,920,000
Recurring | Level 3 |  |
Current Liabilities: |  |
Warrants | 3,792,000 | 3,649,000
Total financial liabilities | $ 3,792,000 | $ 3,649,000

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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