Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 12 Months Ended | ||||
|---|---|---|---|---|---|---|
Mar. 31, 2019 |
Mar. 31, 2018 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2012 |
Dec. 31, 2016 |
|
| Stockholders' Equity (Textual) | ||||||
| Common stock, shares authorized | 1,000,000,000 | |||||
| Common stock, par value | $ 0.0001 | $ 0.0001 | ||||
| Common stock, shares outstanding | 38,363,792 | 27,294,164 | ||||
| Restricted shares subject to repurchase for unvested shares related to early option exercises under stock equity plans | 33,102 | 40,707 | ||||
| Issuance of common stock shares | 1,085,096 | |||||
| Issuance of common stock, net of issuance costs | $ 9,565 | |||||
| Exercise price per share | $ 11.50 | |||||
| Fair value of warrant | 54 | |||||
| Change in fair value of warrants | $ 55 | |||||
| Common stock exercise price | $ 11.50 | |||||
| Sale of option to purchase common stock | 130,000 | |||||
| Common stock warrant, description | The Company issued an aggregate of 11,016,681 shares of common stock related to various cash and cashless (net) exercises of warrants for common stock. Cash exercises for warrants for 617,296 shares of common stock resulted in aggregate gross proceeds of approximately $6,184, of which $5,731 was received in cash, $92 was received in digital currencies, and $361 is recorded as a miscellaneous receivable in prepaid and other current assets due from the Company's transfer agent for proceeds received on our behalf. The Company received these proceeds subsequent to the balance sheet date. Furthermore, there were 12,625,288 warrants exercised under cashless (net) provisions resulting in the issuance of 10,399,385 shares of common stock. See further discussion regarding details of the Company's various warrants below. | |||||
| Employee Stock Option [Member] | ||||||
| Stockholders' Equity (Textual) | ||||||
| Sale of option to purchase common stock | 130,000 | |||||
| Warrants exercised | 50,772 | |||||
| Warrants [Member] | ||||||
| Stockholders' Equity (Textual) | ||||||
| Warrant to purchase aggregate shares of common stock | 1,085,059 | 14,866 | ||||
| Exercise price per share | $ 9.22 | $ 5.54 | ||||
| Shares of common stock reserved to permit exercise | 14,866 | |||||
| Warrants issued to Phunware shareholders | 3,985,244 | |||||
| Warrants [Member] | Private Placement [Member] | ||||||
| Stockholders' Equity (Textual) | ||||||
| Exercise price per share | $ 11.50 | |||||
| Warrants [Member] | Public Warrants [Member] | ||||||
| Stockholders' Equity (Textual) | ||||||
| Shares of common stock reserved to permit exercise | 6,900,610 | |||||
| PhunCoin Warrant [Member] | ||||||
| Stockholders' Equity (Textual) | ||||||
| Exercise price per share | $ 11.50 | |||||
| Warrant shares of outstanding | 27,400,000,000 | |||||