Company Overview	3 Months Ended
Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Company Overview	Note 1 – Company Overview BlackLine, Inc. and its subsidiaries (the “Company” or “BlackLine”) provide financial accounting close solutions delivered primarily as Software as a Service (“SaaS”). The Company’s solutions enable its customers to address various aspects of their financial close process including account reconciliations, variance analysis of account balances, journal entry capabilities, and certain types of data matching capabilities. The Company is headquartered in Woodland Hills, California and has offices in the Netherlands, Canada, France, Singapore, the United Kingdom, Germany, Australia, Hong Kong, Romania, and Poland.

The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e5967-108592

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-URI http://asc.fasb.org/topic&trid=2134479

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