Business Combinations	12 Months Ended
Dec. 31, 2017
Business Combinations [Abstract]
Business Combinations	Note 6. Business Combinations In June 2015, the Company acquired Glip, Inc. (“Glip”), a cloud messaging and collaboration company based in Boca Raton, Florida. Glip is a provider of team messaging services, integrated with project management, group calendars, notes, annotations, and file sharing. The objective of the acquisition was to extend the Company’s platform by adding team messaging and collaboration services such as calendar, project management, and document sharing. The consideration for the acquisition, net of cash acquired, which also included the fair value of contingent consideration payable upon achievement of certain earn out milestones and the fair value of common stock issuable to the sellers, was $11.9 million. Of the consideration, $1.5 million of cash was held back by the Company upon closing as security for certain indemnification obligations of such stockholders. In June 2016, the Company paid the $1.5 million in full. The initial fair value of the milestone based earn out liability was determined to be $2.3 million using various estimates, including probabilities of success and discount rates. All the milestones were completed as of December 31, 2017, and during the year ended December 31, 2017, the Company issued 47,591 shares of the Company’s Class A common stock to settle certain milestones achieved. At December 31, 2016, the estimated fair value of the milestone based earn out liability was $1.9 million and was classified as a current and non-current liability in the consolidated balance sheets. Additionally, under the terms of the acquisition, the Company may also pay up to $2.0 million at the end of a two-year period to certain Glip employees, who continued to be employees of the Company. This was accounted for as a post-combination expense. The Company issued shares of the Company’s Class A common stock to settle the $1.8 million payout during the year ended December 31, 2017. As of December 31, 2017, there was no outstanding contingent payment liability for bonus settlement. At December 31, 2016, the contingent payment liability was $1.4 million and was classified as a current liability in the consolidated balance sheets.

Note 6. Business Combinations

In June 2015, the Company acquired Glip, Inc. (“Glip”), a cloud messaging and collaboration company based in Boca Raton, Florida. Glip is a provider of team messaging services, integrated with project management, group calendars, notes, annotations, and file sharing. The objective of the acquisition was to extend the Company’s platform by adding team messaging and collaboration services such as calendar, project management, and document sharing. The consideration for the acquisition, net of cash acquired, which also included the fair value of contingent consideration payable upon achievement of certain earn out milestones and the fair value of common stock issuable to the sellers, was $11.9 million. Of the consideration, $1.5 million of cash was held back by the Company upon closing as security for certain indemnification obligations of such stockholders. In June 2016, the Company paid the $1.5 million in full.

The initial fair value of the milestone based earn out liability was determined to be $2.3 million using various estimates, including probabilities of success and discount rates. All the milestones were completed as of December 31, 2017, and during the year ended December 31, 2017, the Company issued 47,591 shares of the Company’s Class A common stock to settle certain milestones achieved. At December 31, 2016, the estimated fair value of the milestone based earn out liability was $1.9 million and was classified as a current and non-current liability in the consolidated balance sheets.

Additionally, under the terms of the acquisition, the Company may also pay up to $2.0 million at the end of a two-year period to certain Glip employees, who continued to be employees of the Company. This was accounted for as a post-combination expense. The Company issued shares of the Company’s Class A common stock to settle the $1.8 million payout during the year ended December 31, 2017. As of December 31, 2017, there was no outstanding contingent payment liability for bonus settlement. At December 31, 2016, the contingent payment liability was $1.4 million and was classified as a current liability in the consolidated balance sheets.