| Component: (Network and Table) | |
|---|---|
| Network | 00400 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (http://www.aclaristx.com/role/StatementConsolidatedStatementsOfCashFlows)  | 
| Table | (Implied) | 
| Reporting Entity [Axis] | 0001557746 (http://www.sec.gov/CIK) | 
| Consolidated Statements of Cash Flows | Period [Axis] | ||
|---|---|---|---|
2016-01-01 - 2016-12-31  | 2015-01-01 - 2015-12-31  | 2014-01-01 - 2014-12-31  | |
Consolidated Statements of Cash Flows  | |||
Cash flows from operating activities:  | |||
Net loss  | (48,079,000)   | (20,563,000)   | (8,517,000)   | 
Adjustments to reconcile net loss to net cash used in operating activities:  | |||
Depreciation expense  | |||
Stock-based compensation expense  | |||
Write-down of property and equipment held for sale  | |||
Non-cash charges related to Vixen acquisition  | |||
Changes in operating assets and liabilities:  | |||
Prepaid expenses and other assets  | (  | (  | (  | 
Accounts payable  | (  | ||
Accrued expenses  | |||
Net cash used in operating activities  | (  | (  | (  | 
Cash flows from investing activities:  | |||
Purchases of property and equipment  | (  | (  | (  | 
Purchases of marketable securities  | (  | (  | (  | 
Proceeds from sales and maturities of marketable securities  | |||
Net cash used in investing activities  | (  | (  | (  | 
Cash flows from financing activities:  | |||
Proceeds from issuance of common stock in connection with private placement, net of issuance costs  | |||
Proceeds from follow-on public offering, net of issuance costs  | |||
Proceeds from initial public offering, net of offering costs  | |||
Proceeds from issuance of convertible preferred stock, net of issuance costs  | |||
Proceeds from the exercise of employee stock options  | |||
Net cash provided by financing activities  | |||
Net increase (decrease) in cash and cash equivalents  | (  | ||
Cash and cash equivalents at beginning of period  | 9,851,000    | ||
Cash and cash equivalents at end of period  | 30,171,000    | 9,851,000    | 10,757,000    | 
Supplemental disclosures of non-cash investing and financing activities:  | |||
Additions to property and equipment included in accounts payable  | |||
Fair value of stock issued in connection with Vixen acquisition  | |||
Offering costs included in accounts payable  | |||
Accretion of convertible preferred stock to redemption value  | 1,764,000    | 2,054,000    | |
Fair value of preferred stock purchased put option on date of issuance  | |||