Zix Repurchase Program	12 Months Ended
Dec. 31, 2018
Equity [Abstract]
Zix Repurchase Program	19. Zix Repurchase Program On April 24, 2017, the Company’s Board of Directors approved a share repurchase program that enables the Company to purchase up to $10 million of its shares of common stock. The shares repurchase program expired on May 31, 2018. During the year ended December 31, 2018, the Company repurchased 1,206,994 shares at an aggregate cost of $5.4 million. During the year ended December 31, 2017, the Company repurchased 750,000 shares at an aggregate cost of $3.8 million.

The entire disclosure for treasury stock, including, but not limited to, average cost per share, description of share repurchase program, shares repurchased, shares held for each class of treasury stock.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-URI http://asc.fasb.org/subtopic&trid=2208821

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