CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $)	1 Months Ended	3 Months Ended
Mar. 31, 2014	Mar. 31, 2015
Operating activities
Net loss	$ (92,723)us-gaap_NetIncomeLoss	$ (6,017,581)us-gaap_NetIncomeLoss
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Depreciation and amortization	0us-gaap_Depreciation	9,359us-gaap_Depreciation
Stock-based compensation	11,935us-gaap_ShareBasedCompensation	1,745,760us-gaap_ShareBasedCompensation
Changes in operating assets and liabilities:
Restricted cash	0	(27)
Prepaid expenses and other current assets	(364)	(684,278)
Other assets	0	(35,200)
Accounts payable	0	311,305
Accrued expenses	155,454	536,148
Deferred rent	0	(6,220)
Net cash (used in) provided by operating activities	74,302	(4,140,734)
Investing activities
Purchases of property and equipment	0	(26,395)
Net cash used in by investing activities	0	(26,395)
Financing activities
Proceeds from initial public offering, net of offering costs	0	80,435,430
Proceeds from sale of restricted common stock to founders	1,950	0
Proceeds from early exercise of stock options	0	400,000
Net cash provided by financing activities	10,636,950	80,835,430
Net increase in cash	10,711,252us-gaap_CashPeriodIncreaseDecrease	76,668,301us-gaap_CashPeriodIncreaseDecrease
Cash at beginning of period	0us-gaap_Cash	33,854,153us-gaap_Cash
Cash at end of period	10,711,252us-gaap_Cash	110,522,454us-gaap_Cash
Supplemental cash flow information
Property and equipment purchases included in accounts payable	0	23,336
IPO issuance costs included in accounts payable and accrued expenses at December 31, 2014	0	499,549
IPO issuance costs paid in cash through December 31, 2014	0flks_InitialPublicOfferingCostsPaid	575,245flks_InitialPublicOfferingCostsPaid
Series A preferred stock
Financing activities
Proceeds from issuance of convertible preferred stock, net of issuance costs	9,920,000	0
Series B Preferred Stock
Financing activities
Proceeds from issuance of convertible preferred stock, net of issuance costs	$ 715,000	$ 0

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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