Health Catalyst (HCAT) 10-Q 13 Nov 19 2019 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2019	Oct. 31, 2019
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2019
Document Transition Report	false
Entity File Number	001-38993
Entity Registrant Name	HEALTH CATALYST, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-3337483
Entity Address, Address Line One	3165 Millrock Drive #400
Entity Address, City or Town	Salt Lake City
Entity Address, State or Province	UT
Entity Address, Postal Zip Code	84121
City Area Code	801
Local Phone Number	708-6800
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	HCAT
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		36,565,033
Entity Central Index Key	0001636422
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Amendment Flag	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands		Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents		$ 52,059	$ 28,431
Short-term investments		189,360	4,761
Accounts receivable, net	[1]	31,019	27,696
Deferred costs		978	649
Prepaid expenses and other assets		6,403	5,321
Total current assets		279,819	66,858
Property and equipment, net		4,228	4,676
Intangible assets, net		26,684	28,304
Operating lease right-of-use assets		4,494	6,344
Other assets		1,050	1,099
Goodwill		3,694	3,694
Total assets		319,969	110,975
Current liabilities:
Accounts payable		5,179	1,812
Accrued liabilities		9,544	9,203
Acquisition-related consideration payable	[1]	3,403	2,172
Deferred revenue		32,131	24,755
Operating lease liabilities		2,790	2,577
Current portion of long-term debt		0	1,287
Total current liabilities		53,047	41,806
Long-term debt, net of current portion		47,916	18,814
Acquisition-related consideration payable, net of current portion	[1]	1,826	3,770
Deferred revenue, net of current portion		7,505	7,280
Operating lease liabilities, net of current portion		2,435	4,228
Other liabilities		687	0
Total liabilities		113,416	75,898
Commitments and contingencies (Note 15)
Redeemable convertible preferred stock, $0.001 par value; no shares and 45,427,441 shares authorized as of September 30, 2019 and December 31, 2018, respectively; no shares and 22,713,694 shares issued and outstanding as of September 30, 2019 and December 31, 2018, respectively; aggregated liquidation preference of $306,192 as of December 31, 2018		0	409,845
Stockholders’ deficit:
Preferred stock, $0.001 par value per share; 25,000,000 and no shares authorized as of September 30, 2019 and December 31, 2018, respectively; no shares issued and outstanding as of September 30, 2019 and December 31, 2018		0	0
Common stock, $0.001 par value; 500,000,000 and 72,565,312 shares authorized as of September 30, 2019 and December 31, 2018, respectively; 36,472,223 and 4,779,356 shares issued and outstanding as of September 30, 2019 and December 31, 2018, respectively		36	5
Additional paid-in capital		802,777	0
Accumulated deficit		(596,248)	(374,772)
Accumulated other comprehensive loss		(12)	(1)
Total stockholders’ equity (deficit)		206,553	(374,768)
Total liabilities, redeemable convertible preferred stock, and stockholders’ equity (deficit)		$ 319,969	$ 110,975
[1]	Includes amounts attributable to related party transactions. See Note 17 for further details.

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($)	Sep. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Redeemable convertible preferred stock, par value (in USD per share)	$ 0.001	$ 0.001
Redeemable convertible preferred stock, shares authorized (in shares)	0	45,427,441
Redeemable convertible preferred stock, shares issued (in shares)	0	22,713,694
Redeemable convertible preferred stock, shares outstanding (in shares)	0	22,713,694
Redeemable convertible preferred stock, aggregated liquidation preference	$ 0	$ 306,192
Preferred stock, par value (in USD per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	25,000,000	0
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in USD per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	500,000,000	72,565,312
Common stock, shares issued (in shares)	36,472,223	4,779,356
Common stock, shares outstanding (in shares)	36,472,223	4,779,356

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenue:
Revenue	[1]	$ 39,423	$ 32,868	$ 111,440	$ 76,490
Cost of revenue, excluding depreciation and amortization:
Total cost of revenue, excluding depreciation and amortization	[1]	18,632	16,997	53,668	41,125
Operating expenses:
Sales and marketing	[1]	14,721	13,771	35,579	32,496
Research and development	[1]	13,477	10,839	33,209	28,031
General and administrative	[1]	11,013	5,605	23,333	16,748
Depreciation and amortization	[1]	2,316	2,151	6,844	5,252
Total operating expenses		41,527	32,366	98,965	82,527
Loss from operations		(20,736)	(16,495)	(41,193)	(47,162)
Loss on extinguishment of debt		0	0	(1,670)	0
Interest and other expense, net		(659)	(374)	(2,924)	(1,389)
Net loss before income taxes		(21,395)	(16,869)	(45,787)	(48,551)
Income tax provision (benefit)		21	7	43	(142)
Net loss		(21,416)	(16,876)	(45,830)	(48,409)
Less: accretion (reversal of accretion) of redeemable convertible preferred stock		18,170	514	180,826	(12,045)
Net loss attributable to common stockholders		$ (39,586)	$ (17,390)	$ (226,656)	$ (36,364)
Net loss per share attributable to common stockholders, basic and diluted (in USD per share)		$ (1.40)	$ (3.71)	$ (17.78)	$ (7.56)
Weighted-average number of shares used in calculating net loss per share attributable to common stockholders, basic and diluted		28,222,555	4,685,633	12,749,903	4,812,890
Technology
Revenue:
Revenue	[1]	$ 21,160	$ 18,283	$ 61,393	$ 38,459
Cost of revenue, excluding depreciation and amortization:
Total cost of revenue, excluding depreciation and amortization	[1]	6,740	6,132	20,536	12,782
Professional services
Revenue:
Revenue	[1]	18,263	14,585	50,047	38,031
Cost of revenue, excluding depreciation and amortization:
Total cost of revenue, excluding depreciation and amortization	[1]	$ 11,892	$ 10,865	$ 33,132	$ 28,343
[1]	Includes amounts attributable to related party transactions. See Note 17 for further details.

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (21,416)	$ (16,876)	$ (45,830)	$ (48,409)
Other comprehensive loss:
Unrealized gain (loss) on investments	(21)	9	(11)	8
Comprehensive loss	$ (21,437)	$ (16,867)	$ (45,841)	$ (48,401)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	IPO	IPOCommon Stock	IPOAdditional Paid-In Capital
Redeemable Convertible Preferred Stock, beginning balance (in shares) at Dec. 31, 2017	21,109,771
Redeemable Convertible Preferred Stock, beginning balance at Dec. 31, 2017	$ 321,569
Increase (Decrease) in Temporary Equity [Roll Forward]
Accretion of redeemable convertible preferred stock	$ 12,045
Issuance of redeemable convertible preferred stock, net of issuance costs (in shares)	1,603,923
Issuance of redeemable convertible preferred stock, net of issuance costs	$ 36,239
Accretion of redeemable convertible preferred stock	$ 12,045
Redeemable Convertible Preferred Stock, ending balance (in shares) at Sep. 30, 2018	22,713,694
Redeemable Convertible Preferred Stock, ending balance at Sep. 30, 2018	$ 345,763
Common Stock, beginning balance (in shares) at Dec. 31, 2017		4,853,841
Stockholders' equity (deficit), beginning balance at Dec. 31, 2017	(259,475)	$ 5	$ 0	$ (259,468)	$ (12)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)		677,311
Exercise of stock options	2,800	$ 1	2,799
Repurchase of common stock (in shares)		(798,372)
Repurchase of common stock	(8,712)	$ (1)	(8,711)
Stock-based compensation	2,887		2,887
Net loss	(48,409)			(48,409)
Other comprehensive gain (loss)	8				8
Accretion of redeemable convertible preferred stock	12,045		12,045
Common Stock, ending balance (in shares) at Sep. 30, 2018		4,732,780
Stockholders' equity (deficit), ending balance at Sep. 30, 2018	$ (298,856)	$ 5	9,020	(307,877)	(4)
Redeemable Convertible Preferred Stock, beginning balance (in shares) at Jun. 30, 2018	22,713,694
Redeemable Convertible Preferred Stock, beginning balance at Jun. 30, 2018	$ 345,249
Increase (Decrease) in Temporary Equity [Roll Forward]
Accretion of redeemable convertible preferred stock	$ 514
Redeemable Convertible Preferred Stock, ending balance (in shares) at Sep. 30, 2018	22,713,694
Redeemable Convertible Preferred Stock, ending balance at Sep. 30, 2018	$ 345,763
Common Stock, beginning balance (in shares) at Jun. 30, 2018		4,671,405
Stockholders' equity (deficit), beginning balance at Jun. 30, 2018	(282,614)	$ 5	8,395	(291,001)	(13)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)		61,375
Exercise of stock options	206	$ 0	206
Stock-based compensation	933		933
Net loss	(16,876)			(16,876)
Other comprehensive gain (loss)	9				9
Accretion of redeemable convertible preferred stock	514		514
Common Stock, ending balance (in shares) at Sep. 30, 2018		4,732,780
Stockholders' equity (deficit), ending balance at Sep. 30, 2018	$ (298,856)	$ 5	9,020	(307,877)	(4)
Redeemable Convertible Preferred Stock, beginning balance (in shares) at Dec. 31, 2018	22,713,694
Redeemable Convertible Preferred Stock, beginning balance at Dec. 31, 2018	$ 409,845
Increase (Decrease) in Temporary Equity [Roll Forward]
Accretion of redeemable convertible preferred stock	$ 180,826
Issuance of redeemable convertible preferred stock, net of issuance costs (in shares)	437,787
Issuance of redeemable convertible preferred stock, net of issuance costs	$ 12,073
Redeemable Convertible Preferred Stock, ending balance (in shares) at Sep. 30, 2019	0
Redeemable Convertible Preferred Stock, ending balance at Sep. 30, 2019	$ 0
Common Stock, beginning balance (in shares) at Dec. 31, 2018	4,832,134	4,779,356
Stockholders' equity (deficit), beginning balance at Dec. 31, 2018	$ (374,768)	$ 5	0	(374,772)	(1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)	301,427	301,427
Exercise of stock options	$ 2,177		2,177
Stock-based compensation	13,028		13,028
Accretion of redeemable convertible preferred stock	$ (180,826)		(5,180)	(175,646)
Conversion of redeemable convertible preferred stock (in shares)	23,151,481	23,151,481
Conversion of redeemable convertible preferred stock	$ 602,744	$ 23	602,721
Initial public offering, net of underwriters’ discounts and commissions and offering costs						$ 190,039	$ 8	$ 190,031
Exercise of common stock warrants (in shares)		189,959					8,050,000
Net loss	(45,830)			(45,830)
Other comprehensive gain (loss)	(11)				(11)
Common Stock, ending balance (in shares) at Sep. 30, 2019		36,472,223
Stockholders' equity (deficit), ending balance at Sep. 30, 2019	$ 206,553	$ 36	802,777	(596,248)	(12)
Redeemable Convertible Preferred Stock, beginning balance (in shares) at Jun. 30, 2019	23,151,481
Redeemable Convertible Preferred Stock, beginning balance at Jun. 30, 2019	$ 584,574
Increase (Decrease) in Temporary Equity [Roll Forward]
Accretion of redeemable convertible preferred stock	$ 18,170
Redeemable Convertible Preferred Stock, ending balance (in shares) at Sep. 30, 2019	0
Redeemable Convertible Preferred Stock, ending balance at Sep. 30, 2019	$ 0
Common Stock, beginning balance (in shares) at Jun. 30, 2019		5,002,426
Stockholders' equity (deficit), beginning balance at Jun. 30, 2019	(557,149)	$ 5	0	(557,163)	9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)		78,357
Exercise of stock options	552		552
Stock-based compensation	9,974		9,974
Accretion of redeemable convertible preferred stock	$ (18,170)		(501)	(17,669)
Conversion of redeemable convertible preferred stock (in shares)	23,151,481	23,151,481
Conversion of redeemable convertible preferred stock	$ 602,744	$ 23	602,721
Initial public offering, net of underwriters’ discounts and commissions and offering costs						$ 190,039	$ 8	$ 190,031
Exercise of common stock warrants (in shares)		189,959					8,050,000
Net loss	(21,416)			(21,416)
Other comprehensive gain (loss)	(21)				(21)
Common Stock, ending balance (in shares) at Sep. 30, 2019		36,472,223
Stockholders' equity (deficit), ending balance at Sep. 30, 2019	$ 206,553	$ 36	$ 802,777	$ (596,248)	$ (12)

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Issuance costs		$ 4,407	$ 0
Shares of redeemable convertible preferred stock
Issuance costs	$ 0	$ 115	$ 13

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities
Net loss		$ (45,830)	$ (48,409)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	[1]	6,844	5,252
Loss on extinguishment of debt		1,670	0
Amortization of debt discount and issuance costs		797	393
Investment discount and premium amortization		(443)	(120)
Change in fair value of warrant liability		0	(37)
Gain on sale of property and equipment		(36)	(21)
Stock-based compensation expense		13,028	2,887
Change in operating assets and liabilities:
Accounts receivable, net		(3,323)	(1,206)
Deferred costs		(329)	191
Prepaid expenses and other assets		(1,033)	(650)
Operating lease right-of-use assets		1,850	(3,957)
Accounts payable, accrued liabilities, and other liabilities		1,661	7,518
Deferred revenue		7,601	7,415
Operating lease liabilities		(1,580)	3,434
Net cash used in operating activities		(19,123)	(27,310)
Cash flows from investing activities
Purchases of property and equipment		(1,658)	(760)
Proceeds from the sale of property and equipment		40	21
Purchase of short-term investments		(221,444)	(9,234)
Proceeds from the sale and maturity of short-term investments		37,277	26,700
Purchase of intangible assets		(1,747)	(18)
Net cash (used in) provided by investing activities		(187,532)	16,709
Cash flows from financing activities
Proceeds from initial public offering, net of underwriters’ discounts and commissions		194,649
Proceeds from the issuance of redeemable convertible preferred stock, net of issuance costs		12,073	33,987
Proceeds from exercise of stock options		2,177	2,800
Proceeds from employee stock purchase plan		1,216
Repurchase of common stock		0	(8,712)
Payment of SVB line of credit and mezzanine loan		(21,821)	0
Proceeds from credit facilities, net of debt issuance costs		47,169	0
Payments of acquisition-related consideration		(773)	(12,348)
Payments of deferred offering costs		(4,407)	0
Net cash provided by financing activities		230,283	15,727
Net increase in cash and cash equivalents		23,628	5,126
Cash and cash equivalents at beginning of period		28,431	22,978
Cash and cash equivalents at end of period		52,059	28,104
Supplemental disclosures of non-cash investing and financing information
Redeemable convertible preferred stock accretion (reversal of accretion)		180,826
Redeemable convertible preferred stock accretion (reversal of accretion)		(180,826)	(12,045)
Deferred offering costs included in accounts payable and accrued liabilities		203	0
Series E redeemable convertible preferred stock allocated to business combination		0	2,252
Purchase of intangible assets included in accounts payable and accrued liabilities		1,304	0
Purchase of property and equipment included in accounts payable and accrued liabilities		155	44
Supplemental disclosures of cash flow information related to leases
Cash paid for operating lease liabilities in operating cash flows		2,426	2,320
Operating lease right-of-use assets obtained in exchange for operating lease obligations		$ 581	$ 5,544
Stockholders’ Equity (Deficit)		Stockholders’ Equity (Deficit) Amendment and Restatement of Certificate of Incorporation In connection with the IPO, the certificate of incorporation of Health Catalyst was amended and restated to, among other things, provide for the (i) authorization of 500,000,000 shares of common stock with a par value of $0.001 per share; (ii) authorization of 25,000,000 shares of undesignated preferred stock that may be issued from time to time; and (iii) establishment of a classified board of directors, divided into three classes, each of whose members will serve for staggered three-year terms. Preferred Stock Our board of directors has the authority, without further action by our stockholders, to issue up to 25,000,000 shares of preferred stock in one or more series and to fix the rights, preferences, and privileges thereof, including voting rights. As of September 30, 2019 and December 31, 2018, no shares of this preferred stock were issued and outstanding. Common stock We had 500,000,000 and 72,565,312 shares of $0.001 par value common stock authorized, of which 36,525,001 and 4,832,134 shares were legally issued and outstanding as of September 30, 2019 and December 31, 2018 , respectively. The shares legally issued and outstanding include 52,778 shares issued to former employees with notes determined to be substantively nonrecourse and, as such, for accounting purposes are not considered to be outstanding shares of common stock. Each share of common stock has the right to one vote on all matters submitted to a vote of stockholders. The holders of common stock are also entitled to receive dividends whenever funds are legally available and when declared by the board of directors, subject to prior rights of holders of all classes of stock outstanding having priority rights as to dividends. No dividends have been declared or paid on our common stock through September 30, 2019. During the nine months ended September 30, 2018 , as part of a tender offer we repurchased 798,372 shares of common stock from team members, which shares were received by the exercise of stock options or contractual arrangements, for cash consideration of $16.9 million . The estimated fair value of the repurchased common stock of $8.6 million and offering costs of $0.1 million were recorded as a reduction to common stock and additional paid-in capital. The excess of the repurchase price over the estimated fair value of the common stock redeemed from team members of $8.3 million was accounted for as compensation expense on the condensed consolidated statement of operations. The effects of the excess of the tender offer repurchase price over the estimated fair value of the common stock redeemed from team members on the statement of operations for the nine months ended September 30, 2018 are summarized in the following table (in thousands): Nine Months Ended September 30, 2018 Cost of revenue $ 312 Sales and marketing 3,967 Research and development 906 General and administrative 3,133 Total compensation expense from repurchase $ 8,318 Common s tock w arrants In October 2017, we issued warrants in connection with the Mezzanine Loan and Security Agreement for up to 255,336 shares of common stock with a ten-year term at an exercise price of $10.66 per share. The fair value of the warrants on the date of grant was $1.6 million and recorded as deferred financing costs. The deferred financing costs are reclassified to a discount on debt in proportion to the advances made on the credit facility. The deferred financing costs and the debt discount are recognized as interest expense over the term of the credit facility. The common stock warrants that are exercisable without contingency are classified as part of stockholders’ equity (deficit) on the condensed consolidated balance sheets. The common stock warrants subject to contingency were classified as a liability on the balance sheet with changes in fair value being recorded each reporting period through the changes in fair value of warrant liability account within interest and other expense, net on the condensed consolidated statements of operations. Once a contingency was resolved, the respective liability-classified warrants were marked to market and recorded in stockholders’ equity (deficit) on the condensed consolidated balance sheets. In October 2018, all remaining contingencies were resolved and the remaining common stock warrant liability balance was marked to market and recorded in stockholders’ equity (deficit). During the three months ended September 30, 2019, all 255,336 outstanding warrants were exercised through a cashless exercise, resulting in the issuance of 189,959 shares of common stock.
[1]	Includes amounts attributable to related party transactions. See Note 17 for further details.

Description of Business and Sum

Description of Business and Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Description of Business and Summary of Significant Accounting Policies	Description of Business and Summary of Significant Accounting Policies Nature of operations Health Catalyst, Inc. (Health Catalyst) was incorporated under the laws of Delaware in September 2011. We are a leading provider of data and analytics technology and services to healthcare organizations. Our Solution comprises a cloud-based data platform, analytics software, and professional services expertise. Our customers, which are primarily healthcare providers, use our Solution to manage their data, derive analytical insights to operate their organization, and produce measurable clinical, financial, and operational improvements. Basis of presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (GAAP) and the applicable regulations of the U.S. Securities and Exchange Commission (SEC) regarding interim financial reporting. Certain information and note disclosures normally included in annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. Therefore, these unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the related notes thereto as of and for the year ended December 31, 2018 included in the Prospectus. Interim Unaudited Condensed Consolidated Financial Statements The accompanying interim condensed consolidated balance sheet as of September 30, 2019, the interim condensed consolidated statements of operations for the three and nine months ended September 30, 2019 and 2018 , the interim condensed consolidated statements of redeemable convertible preferred stock and stockholders' equity (deficit) for the three and nine months ended September 30, 2019, and the interim condensed consolidated statements of cash flows for the nine months ended September 30, 2019 and 2018 are unaudited. The condensed consolidated balance sheet as of December 31, 2018 was derived from audited financial statements, but does not include all disclosures required by GAAP. The interim unaudited condensed consolidated financial statements have been prepared on a basis consistent with the annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to state fairly the Company's financial position, its operations and cash flows for the periods presented. The historical results are not necessarily indicative of future results, and the results of operations for the three and nine months ended September 30, 2019 are not necessarily indicative of the results to be expected for the full year or any other period. Initial Public Offering On July 29, 2019, we closed our initial public offering of common stock (IPO) in which we issued and sold 8,050,000 shares (inclusive of the underwriters’ over-allotment option to purchase 1,050,000 shares, which was exercised on July 25, 2019) of common stock at $26.00 per share. We received net proceeds of $194.6 million after deducting underwriting discounts and commissions and before deducting offering costs of $4.6 million . Upon the closing of our IPO, all shares of our outstanding redeemable convertible preferred stock converted into 23,151,481 shares of common stock on a one-for-one basis. Stock Split On July 10, 2019, we effected a 1-for-2 reverse stock split of our capital stock. We have adjusted all references to share and per share amounts in the accompanying condensed consolidated financial statements and notes to reflect the reverse stock split. Principles of consolidation The condensed consolidated financial statements include the accounts of Health Catalyst and its wholly-owned subsidiaries. Intercompany balances and transactions have been eliminated. Use of estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an on-going basis, we evaluate our estimates, including those related to revenue recognition, provisions for doubtful accounts, useful lives of property and equipment, capitalization and estimated useful life of internal-use software and other intangible assets, fair value of financial instruments, deferred tax assets, common stock warrants, redeemable convertible preferred stock accretion, stock-based compensation, and tax uncertainties. Actual results could differ from those estimates. Segment reporting Operating segments are identified as components of an enterprise about which separate discrete financial information is evaluated by the chief operating decision maker (the CODM) in assessing performance and making decisions regarding resource allocation. We operate our business in two operating segments that also represent our reportable segments. Our segments are (1) technology and (2) professional services. The CODM uses Adjusted Gross Profit (defined as revenue less cost of revenue that excludes depreciation, amortization, stock-based compensation expense, and certain other operating expenses) as the measure of our profit. Net loss per share Basic net loss per share is calculated by dividing net loss attributable to common stockholders by the weighted average number of shares of common stock outstanding. Net loss attributable to common stockholders is computed as net loss less accretion (reversal of accretion) of redeemable convertible preferred stock. Diluted net loss per share attributable to common stockholders is calculated by giving effect to all potentially dilutive common stock equivalents outstanding for the period. For purposes of this calculation, stock options, restricted stock units (RSUs), purchase rights committed under the employee stock purchase plan, and warrants to purchase common stock are considered to be common stock equivalents but have been excluded from the calculation of diluted net loss per share attributable to common stockholders as the effect is antidilutive. Prior to our IPO, we computed basic and diluted net loss per share in conformity with the two-class method required for participating securities. The two-class method is an earnings allocation formula that treats a participating security as having rights to earnings that otherwise would have been available to holders of common stock. Redeemable convertible preferred stock and common stock were considered participating securities for purposes of this calculation. However, the two-class method did not impact the net loss per common share attributable to common stockholders as we were in a loss position for each of the periods presented and the redeemable convertible preferred stockholders did not have a contractual obligation to participate in losses. Revenue r ecognition We recognize revenue in accordance with Accounting Standards Codification Topic 606, Revenue from Contracts with Customers (Topic 606) . We derive our revenues primarily from technology subscriptions and professional services. We determine revenue recognition by applying the following steps: • Identification of the contract, or contracts, with a customer; • Identification of the performance obligations in the contract; • Determination of the transaction price; • Allocation of the transaction price to the performance obligations in the contract; and • Recognition of revenue when, or as, we satisfy the performance obligation. We recognize revenue net of any taxes collected from customers and subsequently remitted to governmental authorities. Technology r evenue Technology revenue primarily consists of subscription fees charged to customers for access to use our technology. We provide customers access to our technology through either an all-access or limited-access, modular subscription. The majority of our subscription arrangements are cloud-based and do not provide customers the right to take possession of the technology or contain a significant penalty if the customer were to take possession of the technology. Revenue from cloud-based subscriptions is recognized ratably over the contract term beginning on the date that the service is made available to the customer. Most of our subscription contracts have up to a three-year term, of which the vast majority are terminable after one year upon 90 days’ notice. Subscriptions that allow the customer to take software on-premise without significant penalty are treated as time-based licenses. These arrangements generally include access to technology, access to unspecified future products, and maintenance and support. Revenue for upfront access to our technology library is recognized at a point in time when the technology is made available to the customer. Revenue for access to unspecified future products included in time-based license subscriptions is recognized ratably over the contract term beginning on the date that the access is made available to the customer. We also have certain perpetual license arrangements. Revenue from these arrangements is recognized at a point in time upon delivery of the software. Technology revenue also includes maintenance and support revenue which generally includes bug fixes, updates, and support services. Revenue related to maintenance and support is recognized over the contract term beginning on the date that the service is made available to the customer. Professional s ervices r evenue Professional services revenue primarily includes data and analytics services, domain expertise services, outsourcing services, and implementation services. Professional services arrangements typically include a fee for making full-time equivalent (FTE) services available to our customers on a monthly basis. FTE services generally consist of a blend of analytic engineers, analysts, and data scientists based on the domain expertise needed to best serve our customer. Professional services are typically considered distinct from the technology offerings and revenue is generally recognized as the service is provided using the “right to invoice” practical expedient. Contracts with multiple performance obligations Many of our contracts include multiple performance obligations. We account for performance obligations separately if they are capable of being distinct within the context of the contract. In these circumstances, the transaction price is allocated to separate performance obligations on a relative standalone selling price basis. We determine standalone selling prices based on the observable price a good or service is sold for separately when available. In cases where standalone selling prices are not directly observable, based on information available, we utilize the expected cost plus a margin, adjusted market assessment, or residual estimation method. We consider all information available including our overall pricing objectives, market conditions, and other factors, which may include customer demographics and the types of users. Standalone selling prices are not directly observable for our all-access and limited-access technology arrangements, which are composed of cloud-based subscriptions, time-based licenses, and perpetual licenses. For these technology arrangements, we use the residual estimation method due to a limited number of standalone transactions and/or prices that are highly variable. Variable consideration We have also entered into at-risk and shared savings arrangements with certain customers whereby we receive variable consideration based on the achievement of measurable improvements which may include cost savings or performance against metrics. For these arrangements, we estimate revenue using the most likely amount that we will receive. Estimates are based on our historical experience and best judgment at the time to the extent it is probable that a significant reversal of revenue recognized will not occur. Due to the nature of our arrangements, certain estimates may be constrained until the uncertainty is further resolved. Contract balances Contract assets resulting from services performed prior to invoicing customers are recorded as unbilled accounts receivable and are presented on the condensed consolidated balance sheets in aggregate with accounts receivable. Unbilled accounts receivable generally become billable at contractually specified dates or upon the attainment of contractually defined milestones. As of September 30, 2019 and December 31, 2018 , the unbilled accounts receivable included in accounts receivable on our condensed consolidated balance sheets was $3.5 million and $3.4 million , respectively. We record contract liabilities as deferred revenue when cash payments are received or due in advance of performance. Deferred revenue primarily relates to the advance consideration received from the customer. As of September 30, 2019 and December 31, 2018 , the total of current and non-current deferred revenue on our condensed consolidated balance sheets was $39.6 million and $32.0 million , respectively. Cost of revenue, excluding depreciation and amortization Cost of technology revenue primarily consists of costs associated with hosting and supporting our technology, including third-party cloud computing and hosting costs, contractor costs, and salary and related personnel costs for our cloud services and support teams. Cost of professional services revenue primarily consists of salary and related personnel costs, travel-related costs, and independent contractor costs. Cost of revenue excludes costs related to depreciation and amortization. We defer certain costs to fulfill a contract when the costs are expected to be recovered, are directly related to in-process contracts and enhance resources that will be used in satisfying performance obligations in the future. These deferred fulfillment costs primarily consist of employee compensation incurred as part of the implementation of new contracts. As of September 30, 2019 and December 31, 2018 , we had deferred contract fulfillment costs of $1.0 million and $0.6 million , respectively. Cash and c ash equivalents We consider all highly liquid investments purchased with a remaining maturity of three months or less at the time of acquisition to be cash equivalents. Short-term investments Our investment policy limits investments to highly-rated instruments that mature in less than 12 months. We classify our short-term investments as available for sale. Accounts receivable Accounts receivable are non-interest bearing and are recorded at the original invoiced amount less an allowance for doubtful accounts based on the probability of future collections. When we become aware of circumstances that may decrease the likelihood of collections, we record a specific allowance against amounts due, which reduces the receivable amount to the amount reasonably believed to be collected. For all other customers, we determine and periodically adjust the allowance based on historical loss patterns and current receivables aging. As of September 30, 2019 and December 31, 2018 , we had an allowance for doubtful accounts of $0.5 million and $0.5 million , respectively. Property and equipment Property and equipment are stated at historical cost less accumulated depreciation. Repairs and maintenance costs that do not extend the useful life or improve the related assets are expensed as incurred. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. The estimated useful life of each asset category is as follows: Computer equipment 2-3 years Furniture and fixtures 3 years Leasehold improvements Lesser of lease term or estimated useful life Computer software 2-3 years Capitalized internal-use software costs 3 years When there are indicators of potential impairment, we evaluate the recoverability of the carrying values by comparing the carrying amount of the applicable asset group to the estimated undiscounted future cash flows expected to be generated by the asset group over the remaining life of the primary long-lived asset in that group plus any residual value. If the carrying amount of the asset group exceeds its estimated undiscounted future net cash flows, an impairment charge is recognized based on the amount by which the carrying value of the long-lived assets exceeds the fair value of those assets. We did not incur any long-lived impairment charges for the three and nine months ended September 30, 2019 and 2018 . Intangible assets Intangible assets include developed technologies, customer relationships, customer contracts, and trademarks that were acquired in business combinations and asset acquisitions. Intangible assets also include the purchase of third-party computer software. The intangible assets are amortized using the straight-line method over the assets’ estimated useful lives. The estimated useful life of each asset category is as follows: Developed technologies 2-10 years Customer relationships and contracts 6 years Computer software licenses 2-5 years Trademarks 2 years Goodwill We record goodwill as the difference between the aggregate consideration paid for a business combination and the fair value of the identifiable net tangible and intangible assets acquired. Goodwill is assessed for impairment annually or more frequently if indicators of impairment are present or circumstances suggest that impairment may exist. The first step of the goodwill impairment test compares the fair value of the reporting unit with its carrying amount, including goodwill. If the fair value of the reporting unit exceeds its carrying amount, the goodwill of the reporting unit is not considered impaired. If the carrying amount of the reporting unit exceeds its fair value, the second step of the goodwill impairment test is performed to measure the amount of impairment loss, if any. The second step of the goodwill impairment test compares the implied fair value of the affected reporting unit’s goodwill with the carrying value of that goodwill. There was no impairment of goodwill for the three and nine months ended September 30, 2019 and 2018 . Deferred offering costs Deferred offering costs, which consist of legal, consulting, banking, and accounting fees directly attributable to the IPO, were capitalized and then offset against proceeds upon the consummation of the IPO. As of December 31, 2018 , our capitalized deferred offering costs were $0.1 million and included in other assets within the consolidated balance sheets. During the three months ended September 30, 2019 , we reclassified $4.6 million of offering costs into stockholders’ equity as a reduction of the net proceeds received from the IPO. Common stock warrants We account for freestanding warrants to purchase shares of our common stock that are not considered indexed to our own stock as warrant liabilities on our condensed consolidated balance sheets until the point in time that they qualify for equity classification. We record liability-classified common stock warrants at their estimated fair value because they are free standing and the number of shares exercisable increases as we make advances on our credit facility. At the end of each reporting period, we record the change in the estimated fair value of the warrants to purchase common stock as a change in fair value of warrant liability within interest and other expense, net in our condensed consolidated statements of operations. We reclassify the warrants from liability-classified to equity-classified as exercise contingencies related to the warrants become resolved. Business c ombinations We account for an acquisition as a business combination if we obtain control of a business. Assets and liabilities acquired in a business combination generally are recorded at fair value and any associated acquisition costs are expensed as incurred in general and administrative expenses. Advertising c osts All advertising costs are expensed as incurred. We recorded advertising costs of $3.4 million and $3.5 million for the three months ended September 30, 2019 and 2018 , respectively, and $4.5 million and $4.6 million for the nine months ended September 30, 2019 and 2018 , respectively. Development costs and internal-use software For technology products that are developed to be sold externally, we determined that technological feasibility is reached shortly before the products are ready for general release. Any costs associated with software development between the time technological feasibility is reached and general release are inconsequential. We capitalize certain development costs incurred in connection with our internal-use software. These capitalized costs are primarily related to the software platforms that are hosted by us and accessed by our customers on a subscription basis. Costs incurred in the preliminary stages of development are expensed as incurred as research and development costs. Once an application has reached the development stage, internal and external costs, if direct and incremental, are capitalized until the software is substantially complete and ready for its intended use. We also capitalize costs related to specific upgrades and enhancements when it is probable the expenditures will result in additional functionality. Capitalized costs are recorded as part of property and equipment. Maintenance and training costs are expensed as incurred. Internal-use software is amortized on a straight-line basis over its estimated useful life. Stock-based compensation Stock-based awards, including stock options and RSUs, are measured and recognized in the condensed consolidated financial statements based on the fair value of the award on the grant date. For awards subject to performance conditions, we record expense when the performance condition becomes probable. We record forfeitures of stock-based awards as the actual forfeitures occur. We estimate the fair value of stock option awards on the grant date using the Black-Scholes option pricing model. W e have issued two types of employee stock-based awards, standard and two-tier. Our standard stock-based awards vest solely on a service-based condition. For these awards, we recognize stock-based compensation expense on a straight-line basis over the vesting period. Two-tier employee stock-based awards, contain both a service-based condition and performance condition, defined as the earlier of (i) an acquisition or change in control of the company or (ii) upon the occurrence of an initial public offering by the Company. A change in control event and effective registration event are not deemed probable until consummated; accordingly, no expense is recorded related to two-tier stock-based awards until the performance condition becomes probable of occurring. Awards which contain both service-based and performance conditions are recognized using the accelerated attribution method once the performance condition is probable of occurring. The service-based condition is generally a service period of four years . Upon closing our IPO, we recorded cumulative share-based compensation expense of approximately $6.0 million using the accumulated attribution method for two-tier employee stock-based awards for which the service condition had been satisfied at that date. Stock-based compensation expense related to purchase rights issued under the 2019 Health Catalyst Employee Stock Purchase Plan (ESPP) is based on the Black-Scholes option-pricing model fair value of the estimated number of awards as of the beginning of the offering period. Stock-based compensation expense is recognized using the straight-line method over the offering period. Prior to the adoption of ASU No. 2018-07, Compensation — Stock Compensation (ASU 2018-17), which simplifies the accounting for non-employee share-based payment transactions and is discussed below under “Accounting pronouncements adopted,” the fair value measurement date for non-employee awards was the date the performance of services was completed. Upon adoption of ASU 2018-07 on January 1, 2019, the measurement date for non-employee awards is the date of grant. The compensation expense for non-employees is recognized, without changes in the fair value of the award, in the same period and in the same manner as though we had paid cash for the services, which is typically the vesting period of the respective award. Income t axes Deferred income tax balances are accounted for using the asset and liability method and reflect the effects of temporary differences between the financial reporting and tax bases of our assets and liabilities using enacted tax rates expected to apply when taxes are actually paid or recovered. In addition, deferred tax assets and liabilities are recorded for net operating loss (NOL) and credit carryforwards. On December 22, 2017, the 2017 Tax Cuts and Jobs Act (Tax Act) was enacted into law and the new legislation contains several key tax provisions that affect us, including the reduction of the corporate income tax rate to 21%, effective January 1, 2018. We were required to recognize the effect of the tax law changes in the period of enactment. As such, we remeasured our consolidated deferred tax assets and liabilities as of December 31, 2017 to reflect the lower rate and also reassessed the net realizability of those deferred tax assets and liabilities. A valuation allowance is provided against deferred tax assets unless it is more likely than not that they will be realized based on all available positive and negative evidence. Such evidence includes, but is not limited to, recent cumulative earnings or losses, expectations of future taxable income by taxing jurisdiction, and the carry-forward periods available for the utilization of deferred tax assets. We use a two-step approach to recognize and measure uncertain income tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates it is more likely than not that the position will be sustained upon audit. The second step is to measure the tax benefit as the largest amount, which is more than 50% likely of being realized upon ultimate settlement. We do not accrue interest and penalties related to unrecognized tax benefits within the provision for income taxes because we have NOLs. Significant judgment is required to evaluate uncertain tax positions. Although we believe that we have adequately reserved for our uncertain tax positions, we can provide no assurance that the final tax outcome of these matters will not be materially different. We evaluate our uncertain tax positions on a regular basis and evaluations are based on a number of factors, including changes in facts and circumstances, changes in tax law, such as the Tax Act, correspondence with tax authorities during the course of an audit, and effective settlement of audit issues. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will affect the provision for income taxes in the period in which such determination is made and could have a material impact on our financial condition and results of operations. Fair value of financial instruments The carrying amounts reported in the condensed consolidated balance sheets for cash, receivables, accounts payable, and current accrued expenses approximate fair values because of the immediate or short-term maturity of these financial instruments. The carrying value of acquisition-related consideration payable, operating lease liabilities, and long-term debt approximate fair value based on interest rates available for debt with similar terms at September 30, 2019 and December 31, 2018 . Money market funds and short-term investments are measured at fair value on a recurring basis. Fair value is estimated by applying the following hierarchy, which prioritizes the inputs used to measure fair value into three levels and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement: • Level 1- Quoted prices in active markets for identical assets or liabilities. • Level 2- Observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. • Level 3- Inputs that are generally unobservable and typically reflect management’s estimate of assumptions that market participants would use in pricing the asset or liability. Leases We determine if an arrangement is a lease at inception. Operating leases are included in operating lease right-of-use (ROU) assets, operating lease liabilities, and operating lease liabilities, net of current portion in our condensed consolidated balance sheets. We have adopted the short-term lease recognition exemption policy. All of our leasing commitments are classified either as operating leases or otherwise qualify as short-term leases with lease terms of 12 months or less. ROU assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. As our lease contracts do not provide an implicit rate, we use our incremental borrowing rate based on the information available at commencement date to determine the present value of lease payments. The operating lease ROU asset also includes any lease payments made and excludes lease executory costs. Our lease terms may include options to extend or terminate the lease when it is reasonably certain that we will exercise the applicable option. Lease expense for lease payments is recognized on a straight-line basis over the lease term. We do not have lease agreements that contain non-lease components, which generally would be accounted for separately. Accounting pronouncement adopted In June 2018, the FASB issued ASU 2018-07, Improvements to Nonemployee Share-Based Payment Accounting (ASU 2018-07) . ASU 2018-07 simplifies the accounting for share-based payments to nonemployees by aligning it with the accounting for share-based payments to employees, with certain exceptions. The new standard is effective for fiscal years beginning after December 15, 2018, and interim periods within those annual periods. We adopted ASU 2018-07 as of January 1, 2019 and applied the standard prospectively. The adoption of this standard did not have a material impact on the condensed consolidated financial statements. Recent accounting pronouncements In June 2016, FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) , that changes how companies will measure credit losses for most financial assets and certain other instruments that are not measured at fair value through net income. For available-for-sale debt securities, we will be required to record allowances rather than reduce the carrying amount. We are required to adopt ASU 2016-13 for annual and interim reporting periods beginning after December 15, 2019. Based on our preliminary assessment, we do not anticipate that the adoption of this ASU will have a material impact on our condensed consolidated financial statements. In January 2017, FASB issued ASU 2017-04, Intangibles-Goodwill and Other - Simplifying the Test for Goodwill Impairment (Topic 350) , that simplifies how an entity is required to test goodwill for impairment by modifying the second step of the impairment test. The second step measures a goodwill impairment loss by comparing the fair value of a reporting unit to the carrying amount. If the carrying amount of the reporting unit exceeds its fair value, the carrying amount of goodwill is reduced by the excess reporting unit carrying amount up to the carrying amount of the goodwill. Public business entities must adopt ASU 2017-04 for annual or interim goodwill impairment tests in reporting periods beginning after December 15, 2019. The guidance will apply to our reporting requirements in performing goodwill impairment testing; however, we do not anticipate the adoption of this guidance will have a material impact on our condensed conso

Business Combinations

Business Combinations	9 Months Ended
	Sep. 30, 2019
Business Combinations [Abstract]
Business Combinations	Business Combinations On June 29, 2018, we completed the purchase of Medicity LLC (Medicity) for consideration in the form of shares of Series E redeemable convertible preferred stock with an estimated fair value of $2.3 million from Aetna, Inc. The purchase of Medicity was consummated as part of an integrated transaction that included two components: (1) a $15 million Series E redeemable convertible preferred stock capital raise by us and (2) a business combination where we acquired 100% of the membership interests in Medicity. The acquisition was accounted for as a business combination as specified under ASC 805, Business Combinations . In the integrated transaction, the consideration transferred was allocated between the business combination and the capital raise based on relative values as of June 29, 2018 of the $15 million cash received in the capital raise and the fair value of net identifiable assets received in the business combination. The fair values of Medicity’s assets and liabilities were determined based on estimates and assumptions that are judgmental in nature, including the timing and amount of projected future cash flows and market-participant discount rates reflecting risks inherent in the future cash flows. The following table summarizes the acquisition-date fair value of consideration transferred and the assets received and liabilities assumed as part of our acquisition of Medicity (in thousands): Assets acquired: Accounts receivable $ 7,016 Prepaid expenses 2,735 Property and equipment 1,613 Computer software licenses 2,358 Developed technologies 800 Customer relationships and contracts 600 Trademarks 100 Total assets acquired 15,222 Less liabilities assumed: Accounts payable and other current liabilities 1,970 Deferred revenue 11,000 Total liabilities assumed 12,970 Total assets acquired, net $ 2,252 The intangibles assets acquired were valued utilizing the income approach and include customer relationships, developed technology, and trademarks with estimated useful lives of six years , five years , and two years , respectively. The estimated useful life remaining on software licenses and property and equipment acquired is one to five years . The following unaudited pro forma information presents our consolidated information as if the acquisition of Medicity had occurred on January 1, 2017 (in thousands, except per share amounts): Year Ended December 31, 2017 2018 Total pro forma revenues $ 109,739 $ 128,992 Pro forma net loss (63,986 ) (72,931 ) Pro forma net loss per share attributable to common stockholders, basic and diluted (13.20 ) (15.20 ) The unaudited pro forma information is not intended to present actual results that would have been attained had the acquisition been completed as of January 1, 2017 or to project potential results as of any future date or for any future periods. The nature and amount of material, nonrecurring pro forma adjustments directly attributable to our acquisition of Medicity which are included in the pro forma revenues or net loss, as applicable, are attributable to fair value adjustments to deferred revenues, amortization of acquired intangible assets and acquisition-related income tax considerations totaling $11.0 million and $0.5 million in 2017 and 2018 , respectively. The amount of revenue attributable to the acquired business of Medicity that has been included in the condensed consolidated statement of operations subsequent to the June 29, 2018 acquisition date through December 31, 2018 is $12.5 million . Loss information for Medicity after the acquisition date through December 31, 2018 is not presented as the Medicity business was integrated into our operations subsequent to the acquisition and is impracticable to quantify. The acquisition provides us with the opportunity to cross-sell to several top health systems and the ability to leverage the Medicity acquired technology to drive change via analytics at the point of care.

Revenue

Revenue	9 Months Ended
	Sep. 30, 2019
Revenue from Contract with Customer [Abstract]
Revenue	Revenue Disaggregation of revenue The following table represents Health Catalyst’s revenue disaggregated by type of arrangement (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Recurring technology $ 21,160 $ 17,163 $ 61,393 $ 36,701 One-time technology (i.e., perpetual license) — 1,120 — 1,758 Professional services 18,263 14,585 50,047 38,031 Total revenue $ 39,423 $ 32,868 $ 111,440 $ 76,490 For the three months ended September 30, 2019 and 2018 and the nine months ended September 30, 2019 and 2018 , 100% , 100% , 100% , and 99.9% , respectively, of revenue was related to contracts with customers located in the United States. Deferred revenue includes advance customer payments and billings in excess of revenue recognized. For the three months ended September 30, 2019 and 2018 , 48% and 36% , respectively, of the revenue recognized was included in deferred revenue at the beginning of the period. For the nine months ended September 30, 2019 and 2018, 18% and 13% , respectively, of the revenue recognized was included in deferred revenue at the beginning of the period. Transaction price allocated to the remaining performance obligations Most of our technology and professional services contracts have up to a three-year term, of which the vast majority are terminable after one year upon 90 days ’ notice. For arrangements that do not allow the customer to cancel within one year or less, we expect to recognize $64.0 million of revenue on unsatisfied performance obligations as of September 30, 2019. We expect to recognize approximately 80%

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
	Sep. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets We operate our business in two operating segments that also represent our reporting units. Our reporting units are organized based on our technology and professional services. We have not incurred any goodwill impairment charges. Goodwill by reporting unit is as follows (in thousands): As of As of 2019 2018 Technology $ 2,912 $ 2,912 Professional services 782 782 Total goodwill $ 3,694 $ 3,694 As of September 30, 2019 , intangible assets consisted of the following (in thousands): Gross Accumulated Amortization Net Developed technologies $ 36,129 $ (15,591 ) $ 20,538 Customer relationships and contracts 4,164 (2,600 ) 1,564 Computer software licenses 6,606 (2,061 ) 4,545 Trademarks 100 (63 ) 37 Total intangible assets $ 46,999 $ (20,315 ) $ 26,684 As of December 31, 2018 , intangible assets consisted of the following (in thousands): Gross Accumulated Amortization Net Developed technologies $ 36,129 $ (12,720 ) $ 23,409 Customer relationships and contracts 4,164 (2,080 ) 2,084 Computer software licenses 3,554 (818 ) 2,736 Trademarks 100 (25 ) 75 Total intangible assets $ 43,947 $ (15,643 ) $ 28,304 Intangible assets are amortized using the straight-line method over the estimated useful lives. Amortization expense of acquired intangible assets was $1.6 million and $1.4 million for the three months ended September 30, 2019 , and 2018 , respectively, and $4.7 million and $3.7 million for the nine months ended September 30, 2019 and 2018 , respectively. Amortization expense for intangible assets is included in depreciation and amortization in the condensed consolidated statements of operations.

Property and Equipment

Property and Equipment	9 Months Ended
	Sep. 30, 2019
Property, Plant and Equipment [Abstract]
Property and equipment	Property and Equipment Property and equipment consisted of the following (in thousands): As of As of 2019 2018 Computer equipment $ 7,454 $ 6,769 Leasehold improvements 2,234 1,704 Furniture and fixtures 1,553 1,406 Capitalized internal-use software costs 1,712 1,482 Computer software 972 972 Capital lease equipment 37 37 Total property and equipment 13,962 12,370 Less: accumulated depreciation (9,734 ) (7,694 ) Property and equipment, net $ 4,228 $ 4,676 Our long-lived assets are located in the United States. Depreciation expense totaled $0.7 million and $0.7 million for the three months ended September 30, 2019 and 2018 , respectively, and $2.2 million and $1.5 million for the nine months ended September 30, 2019 and 2018 , respectively. Depreciation expense includes amortization of assets recorded under a capital lease and the amortization of capitalized internal-use software costs.

Short-term Investments

Short-term Investments	9 Months Ended
	Sep. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Short-term Investments	Short-term Investments Our investment policy limits investments to highly-rated instruments that mature in less than 12 months. We classify our short-term investments as available for sale. Available-for-sale securities are recorded on our condensed consolidated balance sheets at fair market value and any unrealized gains or losses are reported as part of other comprehensive loss on the condensed consolidated statements of comprehensive loss. We determine realized gains or losses on the sales of investments through the specific identification method and record such gains or losses as part of interest and other expense, net on the condensed consolidated statements of operations. We did not have realized gains or losses on investments during the three and nine months ended September 30, 2019 and 2018 . We measure the fair value of investments on a recurring basis. The following table summarizes, by major security type, our cash equivalents and short-term investments that are measured at fair value on a recurring basis (in thousands) as of September 30, 2019 : Amortized Cost Unrealized Gains Unrealized Losses Fair Value Cash equivalents Short-term Investments Money market funds $ 50,975 $ — $ — $ 50,975 $ 50,975 $ — U.S. Treasury notes 50,832 — (9 ) 50,823 — 50,823 Commercial paper 51,364 — — 51,364 — 51,364 Corporate bonds 53,617 — (1 ) 53,616 — 53,616 Asset-backed securities 33,559 — (2 ) 33,557 — 33,557 Total $ 240,347 $ — $ (12 ) $ 240,335 $ 50,975 $ 189,360 The following table summarizes, by major security type, our cash equivalents and short-term investments that are measured at fair value on a recurring basis (in thousands) as of December 31, 2018 : Amortized Cost Unrealized Gains Unrealized Losses Fair Value Cash equivalents Short-term Investments Money market funds $ 23,085 $ — $ — $ 23,085 $ 23,085 $ — US treasury notes 4,175 — (1 ) 4,174 1,396 2,778 Commercial paper 3,976 — — 3,976 1,993 1,983 Corporate bonds 998 — — 998 998 — Total $ 32,234 $ — $ (1 ) $ 32,233 $ 27,472 $ 4,761 As we do not intend to sell investments that are in an unrealized loss position and it is not likely that we will be required to sell any investments before recovery of their amortized cost basis, we do not consider the investments with an unrealized loss to be other-than-temporarily impaired as of September 30, 2019 and December 31, 2018 .

Fair Value of Financial Instrum

Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments Assets measured at fair value on a recurring basis as of September 30, 2019 were as follows (in thousands): September 30, 2019 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 50,975 $ — $ — $ 50,975 U.S. Treasury notes 50,823 — — 50,823 Commercial paper — 51,364 — 51,364 Corporate bonds — 53,616 — 53,616 Asset-backed securities — 33,557 — 33,557 Total $ 101,798 $ 138,537 $ — $ 240,335 Assets measured at fair value on a recurring basis as of December 31, 2018 were as follows (in thousands): December 31, 2018 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 23,085 $ — $ — $ 23,085 U.S. Treasury notes 4,174 — — 4,174 Commercial paper — 3,976 — 3,976 Corporate bonds — 998 — 998 Total $ 27,259 $ 4,974 $ — $ 32,233 As of September 30, 2019 and December 31, 2018 , there were no liabilities measured at fair value on a recurring basis. There were no transfers between Level 1 and Level 2 during the three and nine months ended September 30, 2019 and 2018 .

Accrued liabilities

Accrued liabilities	9 Months Ended
	Sep. 30, 2019
Payables and Accruals [Abstract]
Accrued liabilities	Accrued liabilities As of September 30, 2019 and December 31, 2018 , accrued liabilities consisted of the following (in thousands): As of As of 2019 2018 Accrued compensation and benefit expenses $ 6,091 $ 5,888 Other accrued expenses 3,453 3,315 Total accrued liabilities $ 9,544 $ 9,203

Credit Facilities

Credit Facilities	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
Credit Facilities	Credit Facilities As of September 30, 2019 , our term credit facilities consisted of the following, excluding debt discount and issue costs of $2.1 million (in thousands): Balance Remaining Capacity Interest Rate Basis Rate Term loan $ 50,000 $ 25,000 10.00% Higher of LIBOR plus 7.5% and 10.0% Revolving line of credit — 5,000 5.50% Prime plus 0.50% Total credit facilities 50,000 $ 30,000 Less: Current portion of credit facilities — Credit facilities, less current portion $ 50,000 As of December 31, 2018 , our term credit facilities consisted of the following, excluding debt discount and issue costs of $1.2 million (in thousands): Balance Remaining Capacity Interest Rate Basis Rate Term loan $ 20,000 $ — 11.75% Prime plus 6.25% Revolving line of credit 1,321 18,679 6.00% Prime plus 0.50% Total credit facilities 21,321 $ 18,679 Less: Current portion of credit facilities (1,321 ) Credit facilities, less current portion $ 20,000 In June 2016, we signed a Loan and Security Agreement with Silicon Valley Bank (SVB) which established a revolving line of credit based on a formula amount. The formula amount is calculated as 85% of eligible account balances, which includes certain accounts receivable amounts. The revolving line of credit’s capacity is up to $20.0 million , subject to the limitation set by the formula amount. The line may be increased by $5.0 million upon request and approval by the bank. In October 2017, we entered into the Amended and Restated Loan and Security Agreement, which amends the Loan and Security Agreement. As of December 31, 2018 , the amended revolving line of credit was scheduled to mature in December 2019 . We paid $0.1 million in fees related to the establishment of the revolving line of credit and secured $1.3 million in advances from the revolving line of credit. Amounts borrowed under the SVB Loan and Security Agreement are secured by a first priority security interest in substantially all of our assets other than intellectual property. In the event of default, SVB may accelerate amounts outstanding, terminate the credit facility, and foreclose on the collateral. The agreement also includes a financial covenant requiring the achievement of minimum annual recurring revenue amounts. Failure to meet this financial covenant may constitute an event of default. We were in compliance with this covenant under the terms of the credit facility as of December 31, 2018 . In October 2017, we signed a Mezzanine Loan and Security Agreement with SVB which allows access to borrowings of up to $20.0 million and drew $10.0 million at closing. As of December 31, 2018 , the maturity date of any borrowings under the agreement was April 2021. We paid $0.2 million in fees related to the establishment of the term loan and are required to pay an additional commitment fee each time we draw funds based on a formula and the amount of funds borrowed. In October 2018, we drew an additional $10.0 million under the Mezzanine Loan and Security Agreement. Amounts borrowed under the SVB Mezzanine Loan and Security Agreement are secured by a first priority security interest in substantially all of our assets other than intellectual property. In the event of default, SVB may accelerate amounts outstanding, terminate the credit facility, and foreclose on the collateral. The agreement also includes a financial covenant requiring the achievement of minimum annual recurring revenue amounts in order to draw upon the remaining available credit. We were in compliance with this covenant under the terms of the credit facility as of December 31, 2018 . OrbiMed debt financing transaction On February 6, 2019, we entered into a debt financing agreement with OrbiMed Royalty Opportunities II, LP (OrbiMed) where we obtained an $80.0 million senior term loan commitment, with $50.0 million available and up to an additional $30.0 million contingently available on or prior to March 31, 2020 (the Delayed Draw Commitment). We paid $2.4 million in fees related to the establishment of the OrbiMed term loan and incurred $0.3 million in debt issuance costs. The Delayed Draw Commitment is contingent upon our achievement of minimum levels of technology revenues ranging from technology revenues for the latest 12 months of at least $60.0 million to borrow up to $10.0 million , to a minimum of $80.0 million in technology revenues to borrow between $25.0 million and $30.0 million . The contractual interest rate of the OrbiMed term loan is the higher of LIBOR plus 7.5% and 10.0% . Interest payments are required at the end of each month and monthly installment payments on principal begin in February 2023 and will be based on the then outstanding principal balance divided by 12. The maturity date of the OrbiMed term loan is February 6, 2024. Upon the payment of all or any portion of the principal amount on the OrbiMed term loan, we are required to pay an exit fee of 5% of the principal amount paid. This exit fee is being accreted as interest expense over the contractual term of the loan. If we elect to prepay portions of the principal balance prior to the 48-month anniversary of the closing date we would be required to pay a repayment premium ranging from 1% to 12% of the principal balance prepaid depending on the period in which the prepayment is made. Amounts borrowed under the OrbiMed term loan are secured by a first priority security interest in substantially all of our assets other than intellectual property. In the event of default, OrbiMed may accelerate amounts outstanding, terminate the credit facility, and foreclose on the collateral. The agreement also includes a financial covenant requiring the achievement of minimum trailing twelve-month revenue amounts as well as certain other financial and non-financial covenants. We were in compliance with these covenants under the terms of the OrbiMed term loan as of September 30, 2019. The use of proceeds from the senior term loan included an immediate repayment of our $20.0 million term loan from SVB that required a prepayment premium of $0.5 million and the write-off of deferred debt issuance costs of $1.2 million , resulting in a $1.7 million loss on extinguishment of debt. In addition, we repaid in full the outstanding balance of $1.3 million under the SVB revolving line of credit. On February 6, 2019, we amended the Loan and Security Agreement with SVB which reduced the revolving line of credit to a current maximum of $5.0 million with an obligation to maintain a minimum of $5.0 million cash or cash equivalents on deposit with SVB to maintain the assurance of future credit availability. The line may be increased to $10.0 million upon request and approval by SVB. The maturity date of the revolving line of credit was amended to be February 6, 2021.

Redeemable Convertible Preferre

Redeemable Convertible Preferred Stock	9 Months Ended
	Sep. 30, 2019
Equity [Abstract]
Redeemable Convertible Preferred Stock	Redeemable Convertible Preferred Stock We had 45,427,441 shares of redeemable convertible preferred stock with a par value of $0.001 authorized, of which 22,713,694 shares were issued and outstanding, as of December 31, 2018 . The issued and outstanding redeemable convertible preferred stock as of December 31, 2018 consisted of 3,587,499 shares designated as Series A redeemable convertible preferred stock, 4,986,827 shares designated as Series B redeemable convertible preferred stock, 4,794,007 shares designated as Series C redeemable convertible preferred stock, 3,314,612 shares designated as Series D redeemable convertible preferred stock, and 6,030,749 shares designated as Series E redeemable convertible preferred stock. During the nine months ended September 30, 2019, we authorized 1,077,587 shares of Series F redeemable convertible preferred stock and issued 437,787 shares of Series F redeemable convertible preferred stock for total cash consideration of $12.1 million , net of offering costs of $0.1 million . Upon the closing of our IPO, the 23,151,481 shares of redeemable convertible preferred stock, then outstanding, were converted on a one-for-one basis into 23,151,481 shares of common stock. Prior to the IPO, our shares of redeemable convertible preferred stock were redeemable at the option of the holder at an amount equal to the greater of the original issuance price or the redemption value. Accordingly, we recognized changes in the redemption value as they occurred and adjusted the carrying amount of the applicable class of redeemable convertible preferred stock as a deemed dividend (or a reversal of accretion to reflect a reduction in fair value of the redemption value) from additional paid-in-capital or an adjustment of the accumulated deficit to equal the redemption value at the end of each reporting period. This method viewed the end of the reporting period as if it were also the redemption date for the applicable class of redeemable convertible preferred stock. The shares of redeemable convertible preferred stock were accreted to the estimated fair value of $409.8 million as of December 31, 2018 . Upon the closing of our IPO, the shares of redeemable convertible preferred stock were accreted to the IPO price of $26.00 per share, or $602.7 million . As the shares of redeemable convertible preferred stock were converted into shares of common stock, and are no longer redeemable at the option of the holder, we reclassified the carrying value of the shares of redeemable convertible preferred stock to stockholders’ equity (deficit) on the closing of our IPO.

Net Loss Per Share

Net Loss Per Share	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Net loss per share	Net Loss Per Share The following table presents the calculation of basic and diluted net loss per share attributable to common stockholders (in thousands, except share and per share amounts): Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Numerator: Net loss attributable to common stockholders $ (39,586 ) $ (17,390 ) $ (226,656 ) $ (36,364 ) Denominator: Weighted-average number of shares used in calculating net loss per share attributable to common stockholders, basic and diluted 28,222,555 4,685,633 12,749,903 4,812,890 Net loss per share attributable to common stockholders, basic and diluted $ (1.40 ) $ (3.71 ) $ (17.78 ) $ (7.56 ) During the three and nine months ended September 30, 2019 and 2018 , we incurred net losses and, therefore, the effect of our stock options, restricted stock units, purchase rights committed or shares issued under our employee stock purchase plan, common stock warrants, and redeemable convertible preferred stock (as converted) were not included in the calculation of diluted net loss per share attributable to common stockholders as the effect would be anti-dilutive. The following table contains share totals with a potentially dilutive impact: As of September 30, 2019 2018 Redeemable convertible preferred stock — 22,713,694 Common stock options 7,923,437 7,178,103 Restricted stock units 257,278 — Employee stock purchase plan 138,470 — Common stock warrants — 255,336 Total potentially dilutive securities 8,319,185 30,147,133

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2019
Share-based Payment Arrangement [Abstract]
Stock-based Compensation	Stock-Based Compensation In 2011, our board of directors adopted the Health Catalyst, Inc. 2011 Stock Incentive Plan (2011 Plan), which provided for the direct award, sale of shares and granting of RSUs and options for our common stock to our directors, team members, or consultants. In connection with our IPO, our board of directors adopted the 2019 Stock Option and Incentive Plan (2019 Plan). The 2019 Plan provides flexibility to our compensation committee to use various equity-based incentive awards as compensation tools to motivate our workforce, including the grant of incentive and nonstatutory stock options, restricted and unrestricted stock, RSUs, and stock appreciation rights to our directors, team members, or consultants. We have initially reserved 2,500,000 shares of our common stock plus approximately 256,607 shares of our common stock (the number of shares that were available for issuance under the 2011 Plan immediately prior to the IPO registration date) for the issuance of awards under the 2019 Plan. The 2019 Plan provides that the number of shares reserved available for issuance under the plan will automatically increase each January 1, beginning on January 1, 2020, by 5% of the outstanding number of shares of our common stock on the immediately preceding December 31, or such lesser number of shares as determined by our compensation committee. As of September 30, 2019 and December 31, 2018 , there were 11,272,878 and 8,772,878 shares authorized for grant, respectively, and 2,552,097 and 1,296,793 shares available for grant, respectively, under the 2019 Plan and 2011 Plan (collectively the ‘Stock Incentive Plan’). All options were granted with an exercise price determined by the board of directors that was equal to the estimated fair value of our common stock at the date of grant , based on the information known on the date of grant. Options generally expire on the tenth anniversary of the applicable grant date. We have issued two types of employee stock-based awards, standard and two-tier. Our standard stock-based awards vest solely on a service-based condition. For these awards, we recognize stock-based compensation based on the grant date fair value of the awards and recognize that cost using the straight-line method over the requisite service period of the award. Two-tier employee stock-based awards contain both a service-based condition and performance condition, defined as the earlier of (i) an acquisition or change in control of the company or (ii) upon the occurrence of our initial public offering. A change in control event and effective registration event are not deemed probable until consummated; accordingly, no expense is recorded related to two-tier stock-based awards until the performance condition becomes probable of occurring. Awards which contain both service-based and performance conditions are recognized using the accelerated attribution method once the performance condition is probable of occurring. The service-based condition is generally a service period of four years . Upon closing our IPO, we recorded cumulative share-based compensation expense using the accumulated attribution method for two-tier employee stock-based awards for which the service condition had been satisfied at that date. The fair value of options, which vest in accordance with service schedules, is estimated on the date of grant using the Black-Scholes option pricing model. Prior to our IPO, t he absence of an active market for our common stock required us to estimate the fair value of our common stock for purposes of granting stock-based awards, including stock options and RSUs, and for determining stock-based compensation expense for the periods presented. We obtained contemporaneous third-party valuations to assist in determining the estimated fair value of our common stock. These contemporaneous third-party valuations used the methodologies, approaches, and assumptions consistent with the American Institute of Certified Public Accountants Practice Guide, Valuation of Privately-Held-Company Equity Securities Issued as Compensation . Expected volatilities are based on historical volatilities of comparable companies. The expected term of the options is based on the simplified method outlined in the SEC Staff accounting guidance, under which we estimate the term as the average of the option’s contractual term and the option’s weighted average vesting period. The risk-free rate represents the yield on U.S. Treasury bonds with maturity equal to the expected term of the granted option. We account for forfeitures as they occur. All standard stock-based awards outstanding at September 30, 2019 and December 31, 2018 are expected to vest according to their specific schedules. Prior to the adoption of ASU 2018-17, the fair value measurement date for non-employee awards was the date the performance of services was completed. Upon adoption of ASU 2018-07 on January 1, 2019, the measurement date for non-employee awards is the date of grant. The compensation expense for non-employees is recognized, without changes in the fair value of the award, in the same period and in the same manner as though we had paid cash for the services, which is typically the vesting period of the respective award. Total stock-based compensation expense recognized for service-based stock options and RSUs granted under our Stock Incentive Plan was $9.6 million and $0.9 million for the three months ended September 30, 2019 and 2018 , respectively, and $12.3 million and $2.7 million for the nine months ended September 30, 2019 and 2018 . These current year amounts include a $6.0 million cumulative catch-up of compensation expense related to the two-tier employee stock-based awards that was recorded upon satisfaction of the performance condition upon the closing date of our IPO. The following table summarizes the condensed consolidated statements of operations effect of stock-based compensation expense (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Cost of revenue $ 370 $ 138 $ 722 $ 374 Sales and marketing 1,358 298 2,639 1,023 Research and development 3,067 179 3,502 532 General and administrative 5,179 318 6,165 958 Total stock-based compensation $ 9,974 $ 933 $ 13,028 $ 2,887 Stock Options The fair value of our option grants is estimated at the grant date using the Black-Scholes option-pricing model based on the following weighted average assumptions: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Expected volatility — 45.6%-45.8% 43.8%-44.5% 45.6%-47.6% Expected term (in years) — 6.3 6.3 6.3 Risk-free interest rate — 2.9%-3.0% 2.4%-2.5% 2.5%-3.0% Expected dividends — — — — A summary of the share option activity under the 2019 Plan for the nine months ended September 30, 2019, is as follows: Time-Based Option Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Life in Years Aggregate Intrinsic Value Outstanding at January 1, 2019 7,237,417 $ 9.60 Options granted 1,198,121 16.00 Options exercised (301,427 ) 7.22 Options cancelled/forfeited (210,674 ) 10.51 Outstanding at September 30, 2019 7,923,437 $ 10.64 7.6 $ 166,431,525 Vested and expected to vest as of September 30, 2019 7,923,437 $ 10.64 7.6 $ 166,431,525 Vested and exercisable as of September 30, 2019 3,999,812 $ 8.92 6.4 $ 90,892,289 The weighted-average grant-date fair value for stock options granted during the nine months ended September 30, 2019 was $9.31 per option. The aggregate intrinsic value of stock options exercised was $4.6 million for the nine months ended September 30, 2019. The total grant-date fair value of stock options vested during the nine months ended September 30, 2019 was $6.4 million . As of September 30, 2019, approximately $19.1 million of unrecognized compensation expense related to our stock options is expected to be recognized over a weighted average period of 2.4 years . The options outstanding include 52,778 of shares issued to former employees with notes determined to be substantively nonrecourse and, as such, for accounting purposes are not considered to be exercised stock options. Restricted Stock Units The service-based condition for RSUs is satisfied over four years with a cliff vesting period of one year and quarterly vesting thereafter. The following table sets forth the outstanding RSUs and related activity for the nine months ended September 30, 2019 : Restricted Stock Units Weighted Average Grant Date Fair Value Unvested and outstanding at January 1, 2019 — $ — RSUs granted 257,278 40.95 Unvested and outstanding at September 30, 2019 257,278 $ 40.95 As of September 30, 2019, we had $9.9 million of unrecognized stock-based compensation expense related to outstanding RSUs expected to be recognized over a weighted average period of 3.4 years . Employee Stock Purchase Plan In connection with our IPO in July 2019 , our board of directors adopted the ESPP and a total of 750,000 shares of common stock were initially reserved for issuance under the ESPP. The number of shares of common stock available for issuance under the ESPP will be increased on the first day of each calendar year beginning January 1, 2020 and each year thereafter until the ESPP terminates. The number of shares of common stock reserved and available for issuance under the ESPP shall be cumulatively increased by the least of (i) 750,000 shares, (ii) one percent of the number of shares of common stock issued and outstanding on the immediately preceding December 31, and (iii) such lesser number of shares of common stock as determined by the ESPP Administrator. The ESPP generally provides for six-month offering periods, the exception being the first offering period. The offering periods generally start on the first trading day after June 30 and December 31 of each year. The first offering period began on the IPO date and will end on December 31, 2019. The ESPP permits participants to elect to purchase shares of common stock through fixed percentage contributions from eligible compensation during each offering period, not to exceed 15% of the eligible compensation a participant receives during an offering period or accrue at a rate which exceeds $25,000 of the fair value of the stock (determined on the option grant date(s)) for each calendar year. A participant may purchase the lowest of (a) a number of shares of common stock determined by dividing such participant’s accumulated payroll deductions on the exercise date by the option price, (b) 2,500 shares; or (c) such other lesser maximum number of shares as shall have been established by the Administrator in advance of the offering period. Amounts deducted and accumulated by the participant will be used to purchase shares of common stock at the end of each offering period. The purchase price of the shares will be 85% of the lower of the fair value of common stock on the first trading day of each offering period or on the purchase date, except for the first offering period, for which the purchase price will be 85% of the lower of (i) the IPO price or (ii) the fair value of common stock on the purchase date. Participants may end their participation at any time during an offering period and will be paid their accumulated contributions that have not been used to purchase shares of common stock. Participation ends automatically upon termination of employment. As of September 30, 2019, a total of 138,470 shares were issuable to employees based on ESPP contribution elections and unrecognized ESPP compensation cost was $0.6 million , which is expected to be recognized over the remaining three months of 2019 . The fair value of the purchase right for the ESPP option is estimated on the date of grant using the Black-Scholes model with the following assumptions for the initial offering period: Expected volatility 44% Expected term (in months) 5 Risk-free interest rate 2% Expected dividends —

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The tax provision for interim periods is determined using an estimate of our annual effective tax rate, adjusted for discrete items, if any, that arise during the period. Each quarter, we update our estimate of the annual effective tax rate, and if the estimated annual effective tax rate changes, we make a cumulative adjustment in such period. The quarterly tax provision and the estimate of our annual effective tax rate are subject to variation due to several factors, including variability in our loss before income taxes, the mix of jurisdictions to which such income or loss relates, changes in how we conduct business, and tax law developments. For the three months ended September 30, 2019 and 2018 , our estimated effective tax rate was (0.10)% and (0.04)% , respectively. For the nine months ended September 30, 2019 and 2018 , our estimated effective tax rate was (0.09)% and 0.29% , respectively. The variations between our estimated effective tax rate and the U.S. statutory rate are primarily due to the impact of the Tax Act and our full valuation allowance. We consider all available evidence to evaluate the recovery of deferred tax assets, including historical levels of income, legislative developments, and risks associated with estimates of future taxable income. We have provided a full valuation allowance for our deferred tax assets as of September 30, 2019 , and December 31, 2018 , due to the uncertainty surrounding the future realization of such assets and the cumulative losses we have generated. Therefore, no benefit has been recognized in the financial statements for the NOLs and other deferred tax assets. On December 22, 2017, the Tax Act was enacted into law and the new legislation contains several key tax provisions that affect our condensed consolidated financial statements, including the reduction of the corporate income tax rate to 21%, effective January 1, 2018. We are required to recognize the effect of the tax law changes in the period of enactment. As such, we have remeasured our consolidated deferred tax assets and liabilities to reflect the lower rate and have also reassessed the realizability of those deferred tax assets and liabilities. In December 2017, the SEC staff issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act (SAB 118), which allows us to record provisional amounts during a measurement period not to extend beyond one year of the enactment date. As of December 31, 2018 , we consider the accounting of the deferred tax remeasurements and state tax conformity to be complete. We recognize tax benefits from uncertain tax positions when it is more likely than not, based on the technical merits, that the position will be sustained upon examination. We believe that we have provided adequate reserves for income tax uncertainties in all open tax years. We do not anticipate material changes in the total amount of our unrecognized tax benefits within 12 months of the reporting date.

Contingencies

Contingencies	9 Months Ended
	Sep. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies Litigation Liabilities for loss contingencies arising from claims, assessments, litigation, fines, penalties, and other sources are recorded when it is probable that a liability has been incurred and the amount can be reasonably estimated. Legal costs incurred in connection with loss contingencies are expensed as incurred. We are involved in legal proceedings from time to time that arise in the normal course of business. As of September 30, 2019 and December 31, 2018 , there were no significant outstanding claims against us.

Deferred Revenue and Performanc

Deferred Revenue and Performance Obligations	9 Months Ended
	Sep. 30, 2019
Revenue Recognition and Deferred Revenue [Abstract]
Deferred revenue and performance obligations	Revenue Disaggregation of revenue The following table represents Health Catalyst’s revenue disaggregated by type of arrangement (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Recurring technology $ 21,160 $ 17,163 $ 61,393 $ 36,701 One-time technology (i.e., perpetual license) — 1,120 — 1,758 Professional services 18,263 14,585 50,047 38,031 Total revenue $ 39,423 $ 32,868 $ 111,440 $ 76,490 For the three months ended September 30, 2019 and 2018 and the nine months ended September 30, 2019 and 2018 , 100% , 100% , 100% , and 99.9% , respectively, of revenue was related to contracts with customers located in the United States. Deferred revenue includes advance customer payments and billings in excess of revenue recognized. For the three months ended September 30, 2019 and 2018 , 48% and 36% , respectively, of the revenue recognized was included in deferred revenue at the beginning of the period. For the nine months ended September 30, 2019 and 2018, 18% and 13% , respectively, of the revenue recognized was included in deferred revenue at the beginning of the period. Transaction price allocated to the remaining performance obligations Most of our technology and professional services contracts have up to a three-year term, of which the vast majority are terminable after one year upon 90 days ’ notice. For arrangements that do not allow the customer to cancel within one year or less, we expect to recognize $64.0 million of revenue on unsatisfied performance obligations as of September 30, 2019. We expect to recognize approximately 80%

Related Parties

Related Parties	9 Months Ended
	Sep. 30, 2019
Related Party Transactions [Abstract]
Related Parties	Related Parties We have entered into arrangements with a customer where a member of the customer’s management is currently a member of our board of directors. An executive of a Partners Healthcare affiliate has served on our board of directors since January 2018. We recognized revenue from this related party of $0.8 million and $1.2 million for the three months ended September 30, 2019 and 2018 , respectively, and $2.3 million and $3.1 million for the nine months ended September 30, 2019 and 2018 , respectively. As of September 30, 2019 and December 31, 2018 , we had receivables from this related party of $1.1 million and $0.1 million , respectively. As of September 30, 2019 and December 31, 2018 , we also had acquisition-related consideration payable to this related party for a prior year asset acquisition. This asset acquisition occurred prior to this entity becoming a related party. The acquisition-related consideration payable to this related party was $2.4 million and $3.3 million as of September 30, 2019 and December 31, 2018 , respectively. We have also entered into revenue arrangements with customers that are also our investors. None of these customers hold a significant amount of ownership in our equity interests.

Segments

Segments	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Segments	Segments We operate our business in two operating segments that also represent our reportable segments. Our business is organized based on our technology offerings and professional services. Accordingly, our segments are: • Technology - Our technology segment (Technology) includes our data platform, analytics applications and support services. Technology generates revenues primarily from contracts that are cloud-based subscription arrangements, time-based license arrangements, and maintenance and support fees; and • Professional Services - Our professional services segment (Professional Services) is generally the combination of data and analytics, domain expertise, outsourcing, and implementation services to deliver expertise to our customers to more fully configure and utilize the benefits of our Technology offerings. Revenues and cost of revenues generally are directly attributed to our segments. All segment revenues are from our external customers. Asset and other balance sheet information at the segment level is not reported to our Chief Operating Decision Maker. Segment revenue and Adjusted Gross Profit for the three and nine months ended September 30, 2019 and 2018 were as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Revenue Technology $ 21,160 $ 18,283 $ 61,393 $ 38,459 Professional Services 18,263 14,585 50,047 38,031 Total $ 39,423 $ 32,868 $ 111,440 $ 76,490 Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Adjusted Gross Profit Technology $ 14,484 $ 12,169 $ 40,986 $ 25,754 Professional Services 6,677 4,172 17,616 10,629 Total reportable segments Adjusted Gross Profit 21,161 16,341 58,602 36,383 Less Adjusted Gross Profit reconciling items: Stock-based compensation (370 ) (138 ) (722 ) (374 ) Tender offer payments deemed compensation (1) — — — (312 ) Post-acquisition restructuring costs (2) — (332 ) (108 ) (332 ) Less other reconciling items: Sales and marketing (14,721 ) (13,771 ) (35,579 ) (32,496 ) Research and development (13,477 ) (10,839 ) (33,209 ) (28,031 ) General and administrative (11,013 ) (5,605 ) (23,333 ) (16,748 ) Depreciation and amortization (2,316 ) (2,151 ) (6,844 ) (5,252 ) Debt extinguishment costs — — (1,670 ) — Interest and other expense, net (659 ) (374 ) (2,924 ) (1,389 ) Net loss before income taxes $ (21,395 ) $ (16,869 ) $ (45,787 ) $ (48,551 ) ____________________ (1) Tender offer payments deemed compensation included in the Adjusted Gross Profit reconciliation above relate to employee compensation from repurchases of common stock at a price in excess of its estimated fair value. For additional details refer to Note 11 in the condensed consolidated financial statements. (2) Post-acquisition restructuring costs included in the Adjusted Gross Profit reconciliation above relate to severance charges following the acquisition of Medicity. For additional details refer to Note 2 in the condensed consolidated financial statements.

Description of Business and S_2

Description of Business and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Basis of presentation	Basis of presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (GAAP) and the applicable regulations of the U.S. Securities and Exchange Commission (SEC) regarding interim financial reporting. Certain information and note disclosures normally included in annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. Therefore, these unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the related notes thereto as of and for the year ended December 31, 2018 included in the Prospectus.
Principles of consolidation	Principles of consolidation The condensed consolidated financial statements include the accounts of Health Catalyst and its wholly-owned subsidiaries. Intercompany balances and transactions have been eliminated.
Use of estimates	Use of estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an on-going basis, we evaluate our estimates, including those related to revenue recognition, provisions for doubtful accounts, useful lives of property and equipment, capitalization and estimated useful life of internal-use software and other intangible assets, fair value of financial instruments, deferred tax assets, common stock warrants, redeemable convertible preferred stock accretion, stock-based compensation, and tax uncertainties. Actual results could differ from those estimates.
Segment reporting	Segment reporting Operating segments are identified as components of an enterprise about which separate discrete financial information is evaluated by the chief operating decision maker (the CODM) in assessing performance and making decisions regarding resource allocation. We operate our business in two operating segments that also represent our reportable segments. Our segments are (1) technology and (2) professional services. The CODM uses Adjusted Gross Profit (defined as revenue less cost of revenue that excludes depreciation, amortization, stock-based compensation expense, and certain other operating expenses) as the measure of our profit.
Net loss per share	Net loss per share Basic net loss per share is calculated by dividing net loss attributable to common stockholders by the weighted average number of shares of common stock outstanding. Net loss attributable to common stockholders is computed as net loss less accretion (reversal of accretion) of redeemable convertible preferred stock. Diluted net loss per share attributable to common stockholders is calculated by giving effect to all potentially dilutive common stock equivalents outstanding for the period. For purposes of this calculation, stock options, restricted stock units (RSUs), purchase rights committed under the employee stock purchase plan, and warrants to purchase common stock are considered to be common stock equivalents but have been excluded from the calculation of diluted net loss per share attributable to common stockholders as the effect is antidilutive. Prior to our IPO, we computed basic and diluted net loss per share in conformity with the two-class method required for participating securities. The two-class method is an earnings allocation formula that treats a participating security as having rights to earnings that otherwise would have been available to holders of common stock. Redeemable convertible preferred stock and common stock were considered participating securities for purposes of this calculation. However, the two-class method did not impact the net loss per common share attributable to common stockholders as we were in a loss position for each of the periods presented and the redeemable convertible preferred stockholders did not have a contractual obligation to participate in losses.
Cash and cash equivalents	Cash and c ash equivalents We consider all highly liquid investments purchased with a remaining maturity of three months or less at the time of acquisition to be cash equivalents.
Short-term investments	Short-term investments Our investment policy limits investments to highly-rated instruments that mature in less than 12 months. We classify our short-term investments as available for sale.
Accounts receivable	Accounts receivable
Property and Equipment	Property and equipment Property and equipment are stated at historical cost less accumulated depreciation. Repairs and maintenance costs that do not extend the useful life or improve the related assets are expensed as incurred. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. The estimated useful life of each asset category is as follows: Computer equipment 2-3 years Furniture and fixtures 3 years Leasehold improvements Lesser of lease term or estimated useful life Computer software 2-3 years Capitalized internal-use software costs 3 years
Intangible assets	Intangible assets Intangible assets include developed technologies, customer relationships, customer contracts, and trademarks that were acquired in business combinations and asset acquisitions. Intangible assets also include the purchase of third-party computer software. The intangible assets are amortized using the straight-line method over the assets’ estimated useful lives. The estimated useful life of each asset category is as follows: Developed technologies 2-10 years Customer relationships and contracts 6 years Computer software licenses 2-5 years Trademarks 2 years
Goodwill	Goodwill We record goodwill as the difference between the aggregate consideration paid for a business combination and the fair value of the identifiable net tangible and intangible assets acquired. Goodwill is assessed for impairment annually or more frequently if indicators of impairment are
Deferred offering costs	Deferred offering costs
Common stock warrants	Common stock warrants We account for freestanding warrants to purchase shares of our common stock that are not considered indexed to our own stock as warrant liabilities on our condensed consolidated balance sheets until the point in time that they qualify for equity classification. We record liability-classified common stock warrants at their estimated fair value because they are free standing and the number of shares exercisable increases as we make advances on our credit facility. At the end of each reporting period, we record the change in the estimated fair value of the warrants to purchase common stock as a change in fair value of warrant liability within interest and other expense, net in our condensed consolidated statements of operations. We reclassify the warrants from liability-classified to equity-classified as exercise contingencies related to the warrants become resolved.
Business combinations	Business c ombinations
Advertising cost	Advertising c osts
Development cost and internal-use software	Development costs and internal-use software For technology products that are developed to be sold externally, we determined that technological feasibility is reached shortly before the products are ready for general release. Any costs associated with software development between the time technological feasibility is reached and general release are inconsequential. We capitalize certain development costs incurred in connection with our internal-use software. These capitalized costs are primarily related to the software platforms that are hosted by us and accessed by our customers on a subscription basis. Costs incurred in the preliminary stages of development are expensed as incurred as research and development costs. Once an application has reached the development stage, internal and external costs, if direct and incremental, are capitalized until the software is substantially complete and ready for its intended use. We also capitalize costs related to specific upgrades and enhancements when it is probable the expenditures will result in additional functionality. Capitalized costs are recorded as part of property and equipment. Maintenance and training costs are expensed as incurred. Internal-use software is amortized on a straight-line basis over its estimated useful life.
Stock-based compensation	Stock-based compensation Stock-based awards, including stock options and RSUs, are measured and recognized in the condensed consolidated financial statements based on the fair value of the award on the grant date. For awards subject to performance conditions, we record expense when the performance condition becomes probable. We record forfeitures of stock-based awards as the actual forfeitures occur. We estimate the fair value of stock option awards on the grant date using the Black-Scholes option pricing model. W e have issued two types of employee stock-based awards, standard and two-tier. Our standard stock-based awards vest solely on a service-based condition. For these awards, we recognize stock-based compensation expense on a straight-line basis over the vesting period. Two-tier employee stock-based awards, contain both a service-based condition and performance condition, defined as the earlier of (i) an acquisition or change in control of the company or (ii) upon the occurrence of an initial public offering by the Company. A change in control event and effective registration event are not deemed probable until consummated; accordingly, no expense is recorded related to two-tier stock-based awards until the performance condition becomes probable of occurring. Awards which contain both service-based and performance conditions are recognized using the accelerated attribution method once the performance condition is probable of occurring. The service-based condition is generally a service period of four years . Upon closing our IPO, we recorded cumulative share-based compensation expense of approximately $6.0 million using the accumulated attribution method for two-tier employee stock-based awards for which the service condition had been satisfied at that date. Stock-based compensation expense related to purchase rights issued under the 2019 Health Catalyst Employee Stock Purchase Plan (ESPP) is based on the Black-Scholes option-pricing model fair value of the estimated number of awards as of the beginning of the offering period. Stock-based compensation expense is recognized using the straight-line method over the offering period. Prior to the adoption of ASU No. 2018-07, Compensation — Stock Compensation (ASU 2018-17), which simplifies the accounting for non-employee share-based payment transactions and is discussed below under “Accounting pronouncements adopted,” the fair value measurement date for non-employee awards was the date the performance of services was completed. Upon adoption of ASU 2018-07 on January 1, 2019, the measurement date for non-employee awards is the date of grant. The compensation expense for non-employees is recognized, without changes in the fair value of the award, in the same period and in the same manner as though we had paid cash for the services, which is typically the vesting period of the respective award.
Income taxes	Income t axes Deferred income tax balances are accounted for using the asset and liability method and reflect the effects of temporary differences between the financial reporting and tax bases of our assets and liabilities using enacted tax rates expected to apply when taxes are actually paid or recovered. In addition, deferred tax assets and liabilities are recorded for net operating loss (NOL) and credit carryforwards. On December 22, 2017, the 2017 Tax Cuts and Jobs Act (Tax Act) was enacted into law and the new legislation contains several key tax provisions that affect us, including the reduction of the corporate income tax rate to 21%, effective January 1, 2018. We were required to recognize the effect of the tax law changes in the period of enactment. As such, we remeasured our consolidated deferred tax assets and liabilities as of December 31, 2017 to reflect the lower rate and also reassessed the net realizability of those deferred tax assets and liabilities. A valuation allowance is provided against deferred tax assets unless it is more likely than not that they will be realized based on all available positive and negative evidence. Such evidence includes, but is not limited to, recent cumulative earnings or losses, expectations of future taxable income by taxing jurisdiction, and the carry-forward periods available for the utilization of deferred tax assets. We use a two-step approach to recognize and measure uncertain income tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates it is more likely than not that the position will be sustained upon audit. The second step is to measure the tax benefit as the largest amount, which is more than 50% likely of being realized upon ultimate settlement. We do not accrue interest and penalties related to unrecognized tax benefits within the provision for income taxes because we have NOLs. Significant judgment is required to evaluate uncertain tax positions. Although we believe that we have adequately reserved for our uncertain tax positions, we can provide no assurance that the final tax outcome of these matters will not be materially different. We evaluate our uncertain tax positions on a regular basis and evaluations are based on a number of factors, including changes in facts and circumstances, changes in tax law, such as the Tax Act, correspondence with tax authorities during the course of an audit, and effective settlement of audit issues. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will affect the provision for income taxes in the period in which such determination is made and could have a material impact on our financial condition and results of operations.
Fair value of financial instruments	Fair value of financial instruments The carrying amounts reported in the condensed consolidated balance sheets for cash, receivables, accounts payable, and current accrued expenses approximate fair values because of the immediate or short-term maturity of these financial instruments. The carrying value of acquisition-related consideration payable, operating lease liabilities, and long-term debt approximate fair value based on interest rates available for debt with similar terms at September 30, 2019 and December 31, 2018 . Money market funds and short-term investments are measured at fair value on a recurring basis. Fair value is estimated by applying the following hierarchy, which prioritizes the inputs used to measure fair value into three levels and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement: • Level 1- Quoted prices in active markets for identical assets or liabilities. • Level 2- Observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. • Level 3- Inputs that are generally unobservable and typically reflect management’s estimate of assumptions that market participants would use in pricing the asset or liability.
Leases	Leases We determine if an arrangement is a lease at inception. Operating leases are included in operating lease right-of-use (ROU) assets, operating lease liabilities, and operating lease liabilities, net of current portion in our condensed consolidated balance sheets. We have adopted the short-term lease recognition exemption policy. All of our leasing commitments are classified either as operating leases or otherwise qualify as short-term leases with lease terms of 12 months or less. ROU assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. As our lease contracts do not provide an implicit rate, we use our incremental borrowing rate based on the information available at commencement date to determine the present value of lease payments. The operating lease ROU asset also includes any lease payments made and excludes lease executory costs. Our lease terms may include options to extend or terminate the lease when it is reasonably certain that we will exercise the applicable option. Lease expense for lease payments is recognized on a straight-line basis over the lease term. We do not have lease agreements that contain non-lease components, which generally would be accounted for separately.
Accounting pronouncements	Accounting pronouncement adopted In June 2018, the FASB issued ASU 2018-07, Improvements to Nonemployee Share-Based Payment Accounting (ASU 2018-07) . ASU 2018-07 simplifies the accounting for share-based payments to nonemployees by aligning it with the accounting for share-based payments to employees, with certain exceptions. The new standard is effective for fiscal years beginning after December 15, 2018, and interim periods within those annual periods. We adopted ASU 2018-07 as of January 1, 2019 and applied the standard prospectively. The adoption of this standard did not have a material impact on the condensed consolidated financial statements. Recent accounting pronouncements In June 2016, FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) , that changes how companies will measure credit losses for most financial assets and certain other instruments that are not measured at fair value through net income. For available-for-sale debt securities, we will be required to record allowances rather than reduce the carrying amount. We are required to adopt ASU 2016-13 for annual and interim reporting periods beginning after December 15, 2019. Based on our preliminary assessment, we do not anticipate that the adoption of this ASU will have a material impact on our condensed consolidated financial statements. In January 2017, FASB issued ASU 2017-04, Intangibles-Goodwill and Other - Simplifying the Test for Goodwill Impairment (Topic 350) , that simplifies how an entity is required to test goodwill for impairment by modifying the second step of the impairment test. The second step measures a goodwill impairment loss by comparing the fair value of a reporting unit to the carrying amount. If the carrying amount of the reporting unit exceeds its fair value, the carrying amount of goodwill is reduced by the excess reporting unit carrying amount up to the carrying amount of the goodwill. Public business entities must adopt ASU 2017-04 for annual or interim goodwill impairment tests in reporting periods beginning after December 15, 2019. The guidance will apply to our reporting requirements in performing goodwill impairment testing; however, we do not anticipate the adoption of this guidance will have a material impact on our condensed consolidated financial statements. In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820), Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement , which eliminates certain disclosure requirements for fair value measurements for all entities, requires public entities to disclose certain new information prospectively, including the ranges used to develop significant unobservable inputs for Level 3 fair value measurements, and modifies some disclosure requirements. The new guidance is effective for fiscal years beginning after December 15, 2019 and for interim periods within those fiscal years. An entity is permitted to early adopt either the entire standard or only the provisions that eliminate or modify requirements. We do not anticipate that the disclosure changes that result from this ASU will be material to our condensed consolidated financial statements.

Description of Business and S_3

Description of Business and Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Schedule of property and equipment, useful life	The estimated useful life of each asset category is as follows: Computer equipment 2-3 years Furniture and fixtures 3 years Leasehold improvements Lesser of lease term or estimated useful life Computer software 2-3 years Capitalized internal-use software costs 3 years Property and equipment consisted of the following (in thousands): As of As of 2019 2018 Computer equipment $ 7,454 $ 6,769 Leasehold improvements 2,234 1,704 Furniture and fixtures 1,553 1,406 Capitalized internal-use software costs 1,712 1,482 Computer software 972 972 Capital lease equipment 37 37 Total property and equipment 13,962 12,370 Less: accumulated depreciation (9,734 ) (7,694 ) Property and equipment, net $ 4,228 $ 4,676
Schedule of intangible asset, useful life	The estimated useful life of each asset category is as follows: Developed technologies 2-10 years Customer relationships and contracts 6 years Computer software licenses 2-5 years Trademarks 2 years As of September 30, 2019 , intangible assets consisted of the following (in thousands): Gross Accumulated Amortization Net Developed technologies $ 36,129 $ (15,591 ) $ 20,538 Customer relationships and contracts 4,164 (2,600 ) 1,564 Computer software licenses 6,606 (2,061 ) 4,545 Trademarks 100 (63 ) 37 Total intangible assets $ 46,999 $ (20,315 ) $ 26,684 As of December 31, 2018 , intangible assets consisted of the following (in thousands): Gross Accumulated Amortization Net Developed technologies $ 36,129 $ (12,720 ) $ 23,409 Customer relationships and contracts 4,164 (2,080 ) 2,084 Computer software licenses 3,554 (818 ) 2,736 Trademarks 100 (25 ) 75 Total intangible assets $ 43,947 $ (15,643 ) $ 28,304

Business Combinations (Tables)

Business Combinations (Tables)	9 Months Ended
	Sep. 30, 2019
Business Combinations [Abstract]
Schedule of recognized identified assets acquired and liabilities assumed	The following table summarizes the acquisition-date fair value of consideration transferred and the assets received and liabilities assumed as part of our acquisition of Medicity (in thousands): Assets acquired: Accounts receivable $ 7,016 Prepaid expenses 2,735 Property and equipment 1,613 Computer software licenses 2,358 Developed technologies 800 Customer relationships and contracts 600 Trademarks 100 Total assets acquired 15,222 Less liabilities assumed: Accounts payable and other current liabilities 1,970 Deferred revenue 11,000 Total liabilities assumed 12,970 Total assets acquired, net $ 2,252
Schedule of unaudited pro forma information as if the acquisition of medicity had occurred on January 1, 2017	The following unaudited pro forma information presents our consolidated information as if the acquisition of Medicity had occurred on January 1, 2017 (in thousands, except per share amounts): Year Ended December 31, 2017 2018 Total pro forma revenues $ 109,739 $ 128,992 Pro forma net loss (63,986 ) (72,931 ) Pro forma net loss per share attributable to common stockholders, basic and diluted (13.20 ) (15.20 )

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2019
Revenue from Contract with Customer [Abstract]
Schedule of revenue disaggregated by type of arrangement	The following table represents Health Catalyst’s revenue disaggregated by type of arrangement (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Recurring technology $ 21,160 $ 17,163 $ 61,393 $ 36,701 One-time technology (i.e., perpetual license) — 1,120 — 1,758 Professional services 18,263 14,585 50,047 38,031 Total revenue $ 39,423 $ 32,868 $ 111,440 $ 76,490

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill by Reporting Unit	Goodwill by reporting unit is as follows (in thousands): As of As of 2019 2018 Technology $ 2,912 $ 2,912 Professional services 782 782 Total goodwill $ 3,694 $ 3,694
Schedule of Intangible Assets	The estimated useful life of each asset category is as follows: Developed technologies 2-10 years Customer relationships and contracts 6 years Computer software licenses 2-5 years Trademarks 2 years As of September 30, 2019 , intangible assets consisted of the following (in thousands): Gross Accumulated Amortization Net Developed technologies $ 36,129 $ (15,591 ) $ 20,538 Customer relationships and contracts 4,164 (2,600 ) 1,564 Computer software licenses 6,606 (2,061 ) 4,545 Trademarks 100 (63 ) 37 Total intangible assets $ 46,999 $ (20,315 ) $ 26,684 As of December 31, 2018 , intangible assets consisted of the following (in thousands): Gross Accumulated Amortization Net Developed technologies $ 36,129 $ (12,720 ) $ 23,409 Customer relationships and contracts 4,164 (2,080 ) 2,084 Computer software licenses 3,554 (818 ) 2,736 Trademarks 100 (25 ) 75 Total intangible assets $ 43,947 $ (15,643 ) $ 28,304

Property and Equipment (Tables)

Property and Equipment (Tables)	9 Months Ended
	Sep. 30, 2019
Property, Plant and Equipment [Abstract]
Property and equipment	The estimated useful life of each asset category is as follows: Computer equipment 2-3 years Furniture and fixtures 3 years Leasehold improvements Lesser of lease term or estimated useful life Computer software 2-3 years Capitalized internal-use software costs 3 years Property and equipment consisted of the following (in thousands): As of As of 2019 2018 Computer equipment $ 7,454 $ 6,769 Leasehold improvements 2,234 1,704 Furniture and fixtures 1,553 1,406 Capitalized internal-use software costs 1,712 1,482 Computer software 972 972 Capital lease equipment 37 37 Total property and equipment 13,962 12,370 Less: accumulated depreciation (9,734 ) (7,694 ) Property and equipment, net $ 4,228 $ 4,676

Short-term Investments (Tables)

Short-term Investments (Tables)	9 Months Ended
	Sep. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Schedule of Cash Equivalents and Short-Term Investments Measured at Fair Value	The following table summarizes, by major security type, our cash equivalents and short-term investments that are measured at fair value on a recurring basis (in thousands) as of September 30, 2019 : Amortized Cost Unrealized Gains Unrealized Losses Fair Value Cash equivalents Short-term Investments Money market funds $ 50,975 $ — $ — $ 50,975 $ 50,975 $ — U.S. Treasury notes 50,832 — (9 ) 50,823 — 50,823 Commercial paper 51,364 — — 51,364 — 51,364 Corporate bonds 53,617 — (1 ) 53,616 — 53,616 Asset-backed securities 33,559 — (2 ) 33,557 — 33,557 Total $ 240,347 $ — $ (12 ) $ 240,335 $ 50,975 $ 189,360 The following table summarizes, by major security type, our cash equivalents and short-term investments that are measured at fair value on a recurring basis (in thousands) as of December 31, 2018 : Amortized Cost Unrealized Gains Unrealized Losses Fair Value Cash equivalents Short-term Investments Money market funds $ 23,085 $ — $ — $ 23,085 $ 23,085 $ — US treasury notes 4,175 — (1 ) 4,174 1,396 2,778 Commercial paper 3,976 — — 3,976 1,993 1,983 Corporate bonds 998 — — 998 998 — Total $ 32,234 $ — $ (1 ) $ 32,233 $ 27,472 $ 4,761

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value, Assets Measured on Recurring Basis	Assets measured at fair value on a recurring basis as of September 30, 2019 were as follows (in thousands): September 30, 2019 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 50,975 $ — $ — $ 50,975 U.S. Treasury notes 50,823 — — 50,823 Commercial paper — 51,364 — 51,364 Corporate bonds — 53,616 — 53,616 Asset-backed securities — 33,557 — 33,557 Total $ 101,798 $ 138,537 $ — $ 240,335 Assets measured at fair value on a recurring basis as of December 31, 2018 were as follows (in thousands): December 31, 2018 Level 1 Level 2 Level 3 Total Assets: Money market funds $ 23,085 $ — $ — $ 23,085 U.S. Treasury notes 4,174 — — 4,174 Commercial paper — 3,976 — 3,976 Corporate bonds — 998 — 998 Total $ 27,259 $ 4,974 $ — $ 32,233

Accrued liabilities (Tables)

Accrued liabilities (Tables)	9 Months Ended
	Sep. 30, 2019
Payables and Accruals [Abstract]
Schedule of accrued liabilities	As of September 30, 2019 and December 31, 2018 , accrued liabilities consisted of the following (in thousands): As of As of 2019 2018 Accrued compensation and benefit expenses $ 6,091 $ 5,888 Other accrued expenses 3,453 3,315 Total accrued liabilities $ 9,544 $ 9,203

Credit Facilities (Tables)

Credit Facilities (Tables)	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
Schedule of term credit facilities	As of September 30, 2019 , our term credit facilities consisted of the following, excluding debt discount and issue costs of $2.1 million (in thousands): Balance Remaining Capacity Interest Rate Basis Rate Term loan $ 50,000 $ 25,000 10.00% Higher of LIBOR plus 7.5% and 10.0% Revolving line of credit — 5,000 5.50% Prime plus 0.50% Total credit facilities 50,000 $ 30,000 Less: Current portion of credit facilities — Credit facilities, less current portion $ 50,000 As of December 31, 2018 , our term credit facilities consisted of the following, excluding debt discount and issue costs of $1.2 million (in thousands): Balance Remaining Capacity Interest Rate Basis Rate Term loan $ 20,000 $ — 11.75% Prime plus 6.25% Revolving line of credit 1,321 18,679 6.00% Prime plus 0.50% Total credit facilities 21,321 $ 18,679 Less: Current portion of credit facilities (1,321 ) Credit facilities, less current portion $ 20,000

Stockholders_ Equity (Deficit)

Stockholders’ Equity (Deficit) (Tables)	9 Months Ended
	Sep. 30, 2019
Stockholders' Equity Note [Abstract]
Summary of the effects of the excess of the tender offer repurchase price over the estimated fair value of the common stock redeemed from team members	The effects of the excess of the tender offer repurchase price over the estimated fair value of the common stock redeemed from team members on the statement of operations for the nine months ended September 30, 2018 are summarized in the following table (in thousands): Nine Months Ended September 30, 2018 Cost of revenue $ 312 Sales and marketing 3,967 Research and development 906 General and administrative 3,133 Total compensation expense from repurchase $ 8,318

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Schedule of the calculation of basic and diluted net loss per share attributable to common stockholders	The following table presents the calculation of basic and diluted net loss per share attributable to common stockholders (in thousands, except share and per share amounts): Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Numerator: Net loss attributable to common stockholders $ (39,586 ) $ (17,390 ) $ (226,656 ) $ (36,364 ) Denominator: Weighted-average number of shares used in calculating net loss per share attributable to common stockholders, basic and diluted 28,222,555 4,685,633 12,749,903 4,812,890 Net loss per share attributable to common stockholders, basic and diluted $ (1.40 ) $ (3.71 ) $ (17.78 ) $ (7.56 )
Schedule of share totals with a potentially dilutive impact	The following table contains share totals with a potentially dilutive impact: As of September 30, 2019 2018 Redeemable convertible preferred stock — 22,713,694 Common stock options 7,923,437 7,178,103 Restricted stock units 257,278 — Employee stock purchase plan 138,470 — Common stock warrants — 255,336 Total potentially dilutive securities 8,319,185 30,147,133

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2019
Share-based Payment Arrangement [Abstract]
Schedule of Stock-based Compensation Expense	The following table summarizes the condensed consolidated statements of operations effect of stock-based compensation expense (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Cost of revenue $ 370 $ 138 $ 722 $ 374 Sales and marketing 1,358 298 2,639 1,023 Research and development 3,067 179 3,502 532 General and administrative 5,179 318 6,165 958 Total stock-based compensation $ 9,974 $ 933 $ 13,028 $ 2,887
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The fair value of our option grants is estimated at the grant date using the Black-Scholes option-pricing model based on the following weighted average assumptions: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Expected volatility — 45.6%-45.8% 43.8%-44.5% 45.6%-47.6% Expected term (in years) — 6.3 6.3 6.3 Risk-free interest rate — 2.9%-3.0% 2.4%-2.5% 2.5%-3.0% Expected dividends — — — —
Schedule of Information Related to Stock Options	A summary of the share option activity under the 2019 Plan for the nine months ended September 30, 2019, is as follows: Time-Based Option Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Life in Years Aggregate Intrinsic Value Outstanding at January 1, 2019 7,237,417 $ 9.60 Options granted 1,198,121 16.00 Options exercised (301,427 ) 7.22 Options cancelled/forfeited (210,674 ) 10.51 Outstanding at September 30, 2019 7,923,437 $ 10.64 7.6 $ 166,431,525 Vested and expected to vest as of September 30, 2019 7,923,437 $ 10.64 7.6 $ 166,431,525 Vested and exercisable as of September 30, 2019 3,999,812 $ 8.92 6.4 $ 90,892,289
Schedule of Outstanding RSUs and Related Activity	The following table sets forth the outstanding RSUs and related activity for the nine months ended September 30, 2019 : Restricted Stock Units Weighted Average Grant Date Fair Value Unvested and outstanding at January 1, 2019 — $ — RSUs granted 257,278 40.95 Unvested and outstanding at September 30, 2019 257,278 $ 40.95
Schedule of the Purchase Right for the ESPP Option Assumptions	The fair value of the purchase right for the ESPP option is estimated on the date of grant using the Black-Scholes model with the following assumptions for the initial offering period: Expected volatility 44% Expected term (in months) 5 Risk-free interest rate 2% Expected dividends —

Segments (Tables)

Segments (Tables)	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Schedule of segment revenue	Segment revenue and Adjusted Gross Profit for the three and nine months ended September 30, 2019 and 2018 were as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Revenue Technology $ 21,160 $ 18,283 $ 61,393 $ 38,459 Professional Services 18,263 14,585 50,047 38,031 Total $ 39,423 $ 32,868 $ 111,440 $ 76,490
Schedule of segment adjusted gross profit	Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Adjusted Gross Profit Technology $ 14,484 $ 12,169 $ 40,986 $ 25,754 Professional Services 6,677 4,172 17,616 10,629 Total reportable segments Adjusted Gross Profit 21,161 16,341 58,602 36,383 Less Adjusted Gross Profit reconciling items: Stock-based compensation (370 ) (138 ) (722 ) (374 ) Tender offer payments deemed compensation (1) — — — (312 ) Post-acquisition restructuring costs (2) — (332 ) (108 ) (332 ) Less other reconciling items: Sales and marketing (14,721 ) (13,771 ) (35,579 ) (32,496 ) Research and development (13,477 ) (10,839 ) (33,209 ) (28,031 ) General and administrative (11,013 ) (5,605 ) (23,333 ) (16,748 ) Depreciation and amortization (2,316 ) (2,151 ) (6,844 ) (5,252 ) Debt extinguishment costs — — (1,670 ) — Interest and other expense, net (659 ) (374 ) (2,924 ) (1,389 ) Net loss before income taxes $ (21,395 ) $ (16,869 ) $ (45,787 ) $ (48,551 ) ____________________ (1) Tender offer payments deemed compensation included in the Adjusted Gross Profit reconciliation above relate to employee compensation from repurchases of common stock at a price in excess of its estimated fair value. For additional details refer to Note 11 in the condensed consolidated financial statements. (2) Post-acquisition restructuring costs included in the Adjusted Gross Profit reconciliation above relate to severance charges following the acquisition of Medicity. For additional details refer to Note 2 in the condensed consolidated financial statements.

Description of Business and S_4

Description of Business and Summary of Significant Accounting Policies (Details)	Jul. 29, 2019USD ($)$ / sharesshares	Jul. 10, 2019	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2019USD ($)segment	Sep. 30, 2018USD ($)	Dec. 31, 2018USD ($)
Subsidiary, Sale of Stock [Line Items]
Service period (in years)					4 years
Number of operating segments | segment					2
Number of reportable segments | segment					2
Stock split conversion ratio		0.5
Offering costs					$ 4,407,000	$ 0
Redeemable convertible preferred stock converted into shares of common stock on a one for one basis | shares	23,151,481
Unbilled accounts receivable			$ 3,500,000		3,500,000		$ 3,400,000
Deferred Revenue			39,600,000		39,600,000		32,000,000
Deferred contract fulfillment costs			1,000,000		1,000,000		600,000
Allowance for doubtful accounts			500,000		500,000		500,000
Goodwill impairment			0	$ 0	0	0
Deferred offering costs							$ 100,000
Reclassification of offering costs			4,600,000
Advertising expense			$ 3,400,000	$ 3,500,000	$ 4,500,000	$ 4,600,000
IPO
Subsidiary, Sale of Stock [Line Items]
Common stock issued | shares	8,050,000
Share price | $ / shares	$ 26
Net proceeds after deducting underwriting discounts and commissions and before deducting estimated offering costs	$ 194,600,000
Offering costs	$ 4,600,000
Over-Allotment option
Subsidiary, Sale of Stock [Line Items]
Common stock issued | shares	1,050,000
Stock Incentive Plan | Performance Shares
Subsidiary, Sale of Stock [Line Items]
Service period (in years)					4 years
Cumulative catch-up of compensation expense					$ 6,000,000

Description of Business and S_5

Description of Business and Summary of Significant Accounting Policies - Schedule of Property and Equipment Useful Life (Details)	9 Months Ended
	Sep. 30, 2019
Computer equipment | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	2 years
Computer equipment | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Computer software licenses | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	2 years
Computer software licenses | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Capitalized internal-use software costs
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years

Description of Business and S_6

Description of Business and Summary of Significant Accounting Policies - Schedule of Intangible Assets Useful Life (Details)	9 Months Ended
	Sep. 30, 2019
Customer relationships and contracts
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	6 years
Trademarks
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	2 years
Maximum | Developed technologies
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	10 years
Maximum | Computer software licenses
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	5 years
Minimum | Developed technologies
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	2 years
Minimum | Computer software licenses
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	2 years

Business Combinations - Narrat

Business Combinations - Narrative (Details) - Medicity LLC - USD ($) $ in Thousands	Jun. 29, 2018	Dec. 31, 2018	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Series E redeemable convertible preferred stock capital raise	$ 15,000
Membership interest (in percentage)	100.00%
Pro forma net loss				$ (72,931)	$ (63,986)
Revenue attributable to the business of Medicity		$ 12,500
Series E redeemable convertible preferred stock
Business Acquisition [Line Items]
Fair value of equity issued for business combination	$ 2,300
Fair Value Adjustment To Deferred Revenues, Amortization Of Acquired Intangible Assets, And Acquisition-Related Costs [Member]
Business Acquisition [Line Items]
Pro forma net loss				$ 500	$ 11,000
Customer relationships
Business Acquisition [Line Items]
Estimated useful life			6 years
Developed technologies
Business Acquisition [Line Items]
Estimated useful life			5 years
Trademarks
Business Acquisition [Line Items]
Estimated useful life			2 years
Minimum
Business Acquisition [Line Items]
Property, plant and equipment, useful life			1 year
Minimum | Computer software licenses
Business Acquisition [Line Items]
Estimated useful life			1 year
Maximum
Business Acquisition [Line Items]
Property, plant and equipment, useful life			5 years
Maximum | Computer software licenses
Business Acquisition [Line Items]
Estimated useful life			5 years

Business Combinations - Schedul

Business Combinations - Schedule of Recognized Assets Acquired and Liabilities Assumed (Details) - Medicity LLC $ in Thousands	Jun. 29, 2018USD ($)
Assets acquired:
Accounts receivable	$ 7,016
Prepaid expenses	2,735
Property and equipment	1,613
Total assets acquired	15,222
Less liabilities assumed:
Accounts payable and other current liabilities	1,970
Deferred revenue	11,000
Total liabilities assumed	12,970
Total assets acquired, net	2,252
Computer software licenses
Assets acquired:
Intangible assets	2,358
Developed technologies
Assets acquired:
Intangible assets	800
Customer relationships and contracts
Assets acquired:
Intangible assets	600
Trademarks
Assets acquired:
Intangible assets	$ 100

Business Combinations - Pro For

Business Combinations - Pro Forma Information (Details) - Medicity LLC - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Total pro forma revenues	$ 128,992	$ 109,739
Pro forma net loss	$ (72,931)	$ (63,986)
Pro forma net loss per share attributable to common stockholders, basic and diluted	$ (15.20)	$ (13.20)

Revenue - Schedule of Revenue

Revenue - Schedule of Revenue Disaggregated by Type of Arrangement (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Revenue	[1]	$ 39,423	$ 32,868	$ 111,440	$ 76,490
Recurring technology
Disaggregation of Revenue [Line Items]
Revenue		21,160	17,163	61,393	36,701
One-time technology (i.e., perpetual license)
Disaggregation of Revenue [Line Items]
Revenue		0	1,120	0	1,758
Professional services
Disaggregation of Revenue [Line Items]
Revenue	[1]	$ 18,263	$ 14,585	$ 50,047	$ 38,031
[1]	Includes amounts attributable to related party transactions. See Note 17 for further details.

Revenue - Narrative (Details)

Revenue - Narrative (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Geographic Concentration Risk | Revenue from Contract with Customer Benchmark | UNITED STATES
Disaggregation of Revenue [Line Items]
Revenue related to contracts with customers (percentage)	100.00%	100.00%	100.00%	99.90%

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2019USD ($)segment	Sep. 30, 2018USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Number of operating segments | segment			2
Amortization of intangible assets | $	$ 1.6	$ 1.4	$ 4.7	$ 3.7

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Schedule of Goodwill by Reporting Unit (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Goodwill [Line Items]
Goodwill	$ 3,694	$ 3,694
Technology
Goodwill [Line Items]
Goodwill	2,912	2,912
Professional Services
Goodwill [Line Items]
Goodwill	$ 782	$ 782

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross	$ 46,999	$ 43,947
Accumulated Amortization	(20,315)	(15,643)
Net	26,684	28,304
Developed technologies
Finite-Lived Intangible Assets [Line Items]
Gross	36,129	36,129
Accumulated Amortization	(15,591)	(12,720)
Net	20,538	23,409
Customer relationships and contracts
Finite-Lived Intangible Assets [Line Items]
Gross	4,164	4,164
Accumulated Amortization	(2,600)	(2,080)
Net	1,564	2,084
Computer software licenses
Finite-Lived Intangible Assets [Line Items]
Gross	6,606	3,554
Accumulated Amortization	(2,061)	(818)
Net	4,545	2,736
Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross	100	100
Accumulated Amortization	(63)	(25)
Net	$ 37	$ 75

Property and Equipment - Compo

Property and Equipment - Components of Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment	$ 13,962	$ 12,370
Less: accumulated depreciation	(9,734)	(7,694)
Property and equipment, net	4,228	4,676
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment	7,454	6,769
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	2,234	1,704
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment	1,553	1,406
Capitalized internal-use software costs
Property, Plant and Equipment [Line Items]
Property and equipment	1,712	1,482
Computer software
Property, Plant and Equipment [Line Items]
Property and equipment	972	972
Capital lease equipment
Property, Plant and Equipment [Line Items]
Property and equipment	$ 37	$ 37

Property and Equipment - Narrat

Property and Equipment - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 0.7	$ 0.7	$ 2.2	$ 1.5

Short-term Investments (Details

Short-term Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 240,347	$ 32,234
Unrealized Gains	0	0
Unrealized Losses	(12)	(1)
Fair Value	240,335	32,233
Money market funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	50,975	23,085
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	50,975	23,085
U.S. Treasury notes
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	50,832	4,175
Unrealized Gains	0	0
Unrealized Losses	(9)	(1)
Fair Value	50,823	4,174
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	51,364	3,976
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	51,364	3,976
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	53,617	998
Unrealized Gains	0	0
Unrealized Losses	(1)	0
Fair Value	53,616	998
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	33,559
Unrealized Gains	0
Unrealized Losses	(2)
Fair Value	33,557
Cash equivalents
Debt Securities, Available-for-sale [Line Items]
Fair Value	50,975	27,472
Cash equivalents | Money market funds
Debt Securities, Available-for-sale [Line Items]
Fair Value	50,975	23,085
Cash equivalents | U.S. Treasury notes
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	1,396
Cash equivalents | Commercial paper
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	1,993
Cash equivalents | Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	998
Cash equivalents | Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Fair Value	0
Short-term Investments
Debt Securities, Available-for-sale [Line Items]
Fair Value	189,360	4,761
Short-term Investments | Money market funds
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	0
Short-term Investments | U.S. Treasury notes
Debt Securities, Available-for-sale [Line Items]
Fair Value	50,823	2,778
Short-term Investments | Commercial paper
Debt Securities, Available-for-sale [Line Items]
Fair Value	51,364	1,983
Short-term Investments | Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Fair Value	53,616	$ 0
Short-term Investments | Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 33,557

Fair Value of Financial Instr_3

Fair Value of Financial Instruments (Details) - USD ($)	Sep. 30, 2019	Dec. 31, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	$ 240,335,000	$ 32,233,000
Liabilities measured at fair value on recurring basis	0	0
U.S. Treasury notes
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	50,823,000	4,174,000
Commercial paper
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	51,364,000	3,976,000
Corporate bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	53,616,000	998,000
Asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	33,557,000
Fair value, recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Money market funds	50,975,000	23,085,000
Total	240,335,000	32,233,000
Fair value, recurring | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Money market funds	50,975,000	23,085,000
Total	101,798,000	27,259,000
Fair value, recurring | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Money market funds	0	0
Total	138,537,000	4,974,000
Fair value, recurring | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Money market funds	0	0
Total	0	0
Fair value, recurring | U.S. Treasury notes
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	50,823,000	4,174,000
Fair value, recurring | U.S. Treasury notes | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	50,823,000	4,174,000
Fair value, recurring | U.S. Treasury notes | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	0	0
Fair value, recurring | U.S. Treasury notes | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	0	0
Fair value, recurring | Commercial paper
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	51,364,000	3,976,000
Fair value, recurring | Commercial paper | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	0	0
Fair value, recurring | Commercial paper | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	51,364,000	3,976,000
Fair value, recurring | Commercial paper | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	0	0
Fair value, recurring | Corporate bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	53,616,000	998,000
Fair value, recurring | Corporate bonds | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	0	0
Fair value, recurring | Corporate bonds | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	53,616,000	998,000
Fair value, recurring | Corporate bonds | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	0	$ 0
Fair value, recurring | Asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	33,557,000
Fair value, recurring | Asset-backed securities | Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	0
Fair value, recurring | Asset-backed securities | Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	33,557,000
Fair value, recurring | Asset-backed securities | Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	$ 0

Accrued liabilities (Details)

Accrued liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Payables and Accruals [Abstract]
Accrued compensation and benefit expenses	$ 6,091	$ 5,888
Other accrued expenses	3,453	3,315
Total accrued liabilities	$ 9,544	$ 9,203

Credit Facilities - Narrative

Credit Facilities - Narrative (Details) - USD ($)	Feb. 06, 2019	Oct. 31, 2018	Oct. 31, 2017	Jun. 30, 2016	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Line of Credit Facility [Line Items]
Debt discount and issue costs					$ 2,100,000		$ 2,100,000		$ 1,200,000
Line of credit formula, percentage of eligible account balances				85.00%
Advances from line of credit							47,169,000	$ 0
Loss on extinguishment of debt					$ 0	$ 0	(1,670,000)	0
Repayments of lines of credit							21,821,000	$ 0
Silicon Valley Bank | Term loan
Line of Credit Facility [Line Items]
Prepayment premium	$ 500,000
Write off of deferred debt issuance cost	1,200,000
Loss on extinguishment of debt	1,700,000
Repayments of lines of credit	20,000,000
Silicon Valley Bank | Revolving line of credit
Line of Credit Facility [Line Items]
Repayments of lines of credit	1,300,000
Silicon Valley Bank | Loan and Security Agreement
Line of Credit Facility [Line Items]
Maximum borrowing capacity				$ 20,000,000
Line of credit facility increase				5,000,000
Payments of financing costs				100,000
Advances from line of credit				$ 1,300,000
Current borrowing capacity	5,000,000
Cash or cash equivalents on deposits	5,000,000
Option to increase the maximum borrowing capacity	10,000,000
Silicon Valley Bank | Mezzanine Loan and Security Agreement
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 20,000,000
Payments of financing costs			200,000
Advances from line of credit		$ 10,000,000	$ 10,000,000
OrbiMed Royalty Opportunities II, LP | Senior Term Loan
Line of Credit Facility [Line Items]
Payments of financing costs	2,400,000
Current borrowing capacity	50,000,000
Amount borrowed	80,000,000
Additional borrowing capacity available	30,000,000
Debt issuance costs	$ 300,000
Debt covenant on minimum requirement on technology revenue for 12 months to borrow 1							60,000,000
Debt covenant on minimum requirement on technology revenue for 12 months to borrow 2							$ 80,000,000
Exit fee	5.00%
Minimum | Revolving line of credit
Line of Credit Facility [Line Items]
Basis Rate					10.00%		10.00%
Minimum | OrbiMed Royalty Opportunities II, LP | Senior Term Loan
Line of Credit Facility [Line Items]
Debt covenant borrowing capacity based on technology revenue					$ 25,000,000		$ 25,000,000
Basis Rate	10.00%
Repayment premium (in percentage)	1.00%
Maximum | OrbiMed Royalty Opportunities II, LP | Senior Term Loan
Line of Credit Facility [Line Items]
Debt covenant borrowing capacity based on technology revenue					10,000,000		10,000,000
Debt covenant borrowing capacity based on technology revenue					$ 30,000,000		$ 30,000,000
Repayment premium (in percentage)	12.00%
LIBOR | Revolving line of credit
Line of Credit Facility [Line Items]
Basis Rate					7.50%		7.50%
LIBOR | OrbiMed Royalty Opportunities II, LP | Senior Term Loan
Line of Credit Facility [Line Items]
Contractual interest rate- basis spread on variable rate	7.50%

Credit Facilities - Schedule of

Credit Facilities - Schedule of Term Credit Facilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Line of Credit Facility [Line Items]
Credit facilities	$ 50,000	$ 21,321
Less: Current portion of credit facilities	0	(1,321)
Credit facilities, less current portion	50,000	20,000
Remaining Capacity	30,000	18,679
Term loan
Line of Credit Facility [Line Items]
Credit facilities	50,000	20,000
Remaining Capacity	$ 25,000	$ 0
Interest Rate	10.00%	11.75%
Revolving line of credit
Line of Credit Facility [Line Items]
Credit facilities	$ 0	$ 1,321
Remaining Capacity	$ 5,000	$ 18,679
Interest Rate	5.50%	6.00%
LIBOR | Revolving line of credit
Line of Credit Facility [Line Items]
Basis Rate	7.50%
Prime rate | Term loan
Line of Credit Facility [Line Items]
Basis Rate		6.25%
Prime rate | Revolving line of credit
Line of Credit Facility [Line Items]
Basis Rate	0.50%	0.50%
Minimum | Revolving line of credit
Line of Credit Facility [Line Items]
Basis Rate	10.00%

Redeemable Convertible Prefer_2

Redeemable Convertible Preferred Stock (Details) - USD ($)	Jul. 29, 2019	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Redeemable convertible preferred stock, shares authorized (in shares)		0			45,427,441
Redeemable convertible preferred stock, par value (in USD per share)					$ 0.001
Redeemable convertible preferred stock shares issued	23,151,481	0			22,713,694
Issuance of redeemable convertible preferred stock, net of issuance costs (in shares)		437,787	1,603,923
Redeemable preferred stock issued during period		$ 12,073,000	$ 36,239,000
Issuance costs		4,407,000	0
Redeemable convertible preferred stock, $0.001 par value; no shares and 45,427,441 shares authorized as of September 30, 2019 and December 31, 2018, respectively; no shares and 22,713,694 shares issued and outstanding as of September 30, 2019 and December 31, 2018, respectively; aggregated liquidation preference of $306,192 as of December 31, 2018	$ 602,700,000	$ 0	$ 345,763,000	$ 584,574,000	$ 409,845,000	$ 345,249,000	$ 321,569,000
Designated Series A redeemable convertible preferred stock
Class of Stock [Line Items]
Redeemable convertible preferred stock shares issued		3,587,499
Designated Series B redeemable convertible preferred stock
Class of Stock [Line Items]
Redeemable convertible preferred stock shares issued		4,986,827
Designated Series C redeemable convertible preferred stock
Class of Stock [Line Items]
Redeemable convertible preferred stock shares issued		4,794,007
Designated Series D redeemable convertible preferred stock
Class of Stock [Line Items]
Redeemable convertible preferred stock shares issued		3,314,612
Designated Series E redeemable convertible preferred stock
Class of Stock [Line Items]
Redeemable convertible preferred stock shares issued		6,030,749
Designated Series F redeemable convertible preferred stock
Class of Stock [Line Items]
Issuance of redeemable convertible preferred stock, net of issuance costs (in shares)		437,787
Redeemable convertible preferred stock, additional shares authorized (in shares)		1,077,587
Redeemable preferred stock issued during period		$ 12,100,000
Issuance costs		$ 100,000
IPO
Class of Stock [Line Items]
Issuance costs	$ 4,600,000
Share price	$ 26

Stockholders_ Equity (Deficit_2

Stockholders’ Equity (Deficit) - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017	Oct. 31, 2017
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	500,000,000	500,000,000			72,565,312
Common stock, par value (in USD per share)	$ 0.001	$ 0.001			$ 0.001
Preferred stock, shares authorized (in shares)	25,000,000	25,000,000			0
Term of board of director member		3 years
Preferred stock, shares issued (in shares)	0	0			0
Preferred stock, shares outstanding (in shares)	0	0			0
Preferred stock, shares issued (in shares)	36,525,001	36,525,001			36,525,001
Shares outstanding (in shares)					4,832,134
Shares issued to former employees with notes determined to be nonrecourse (in shares)	52,778	52,778
Cash consideration of stocks repurchased		$ 0	$ 8,712
Fair value of stocks repurchased			8,712
Offering costs					$ 100
Repurchase price over the estimated fair value of the common stock redeemed from team members
Class of Stock [Line Items]
Total compensation expense from repurchase			$ 8,300
Common stock
Class of Stock [Line Items]
Shares outstanding (in shares)	36,472,223	36,472,223	4,732,780	5,002,426	4,779,356	4,671,405	4,853,841
Fair value of stocks repurchased			$ 1
Mezzanine loan and security agreement | Common stock warrants
Class of Stock [Line Items]
Shares of common stock (in shares)								255,336
Warrants term								10 years
Exercise price of warrants (in USD per share)								$ 10.66
Deferred financing costs								$ 1,600
Warrants issued (in shares)	255,336
Mezzanine loan and security agreement | Common stock
Class of Stock [Line Items]
Common stock, shares issued (in shares)	189,959
Team member
Class of Stock [Line Items]
Tender Offer (in shares)			798,372
Cash consideration of stocks repurchased			$ 16,900
Fair value of stocks repurchased			8,600
Offering costs			$ 100

Stockholders_ Equity (Deficit_3

Stockholders’ Equity (Deficit) - Schedule of the Effects of the Tender Offer Repurchase Price Over the Estimated Fair Value of the Common Stock Redeemed (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Total Compensation Expense from Repurchase [Line Items]
Sales and marketing	[1]	$ 14,721	$ 13,771	$ 35,579	$ 32,496
Research and development	[1]	13,477	10,839	33,209	28,031
General and administrative	[1]	$ 11,013	$ 5,605	$ 23,333	16,748
Repurchase price over the estimated fair value of the common stock redeemed from team members
Total Compensation Expense from Repurchase [Line Items]
Cost of revenue					312
Sales and marketing					3,967
Research and development					906
General and administrative					3,133
Total compensation expense from repurchase					$ 8,318
[1]	Includes amounts attributable to related party transactions. See Note 17 for further details.

Net Loss Per Share - Schedule

Net Loss Per Share - Schedule of the Calculation of Basic and Diluted Net Loss Per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Numerator:
Net loss attributable to common stockholders	$ (39,586)	$ (17,390)	$ (226,656)	$ (36,364)
Denominator:
Weighted-average number of shares used in calculating net loss per share attributable to common stockholders, basic and diluted	28,222,555	4,685,633	12,749,903	4,812,890
Net loss per share attributable to common stockholders, basic and diluted (in USD per share)	$ (1.40)	$ (3.71)	$ (17.78)	$ (7.56)

Net Loss Per Share - Schedul_2

Net Loss Per Share - Schedule of Share Totals with a Potentially Dilutive Impact (Details) - shares	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact	8,319,185	30,147,133
Redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact	0	22,713,694
Common stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact	7,923,437	7,178,103
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact	257,278	0
Employee stock purchase plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact	138,470	0
Common stock warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares with a potentially dilutive impact	0	255,336

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) - USD ($)	Jul. 23, 2019	Jul. 31, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period (in years)					4 years
Stock-based compensation expense			$ 9,974,000	$ 933,000	$ 13,028,000	$ 2,887,000
Weighted-average grant date fair value of option (in USD per share)					$ 9.31
Shares exercised in period (in shares)					$ 4,600,000
Total grant-date fair value of stock options vested					6,400,000
Nonvested award options, unrecognized compensation expense			$ 19,100,000		$ 19,100,000
Shares issued to former employees with notes determined to be nonrecourse (in shares)			52,778		52,778
Stock options outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested awards, period for recognition					2 years 4 months 24 days
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period (in years)					4 years
Nonvested awards, period for recognition					3 years 4 months 24 days
Cliff vesting period					1 year
Unrecognized stock-based compensation expense related to RSUs			$ 9,900,000		$ 9,900,000
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized (in shares)		750,000	138,470		138,470
Percentage increase of the number of common stock shares (in percentage)		1.00%
Unrecognized stock-based compensation expense related to RSUs			$ 600,000		$ 600,000
ESPP share increase in period			750,000
Maximum employee subscription rate			15.00%		15.00%
Maximum purchase value during offering period			$ 25,000,000
Denominator of lowest purchase of a participant (in shares)			2,500		2,500
Purchase price of common stock (in percentage)			85.00%
2011 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized (in shares)	2,500,000
Number of additional shares authorized (in shares)	256,607
Percentage increase of the number of common stock shares (in percentage)	5.00%
Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized (in shares)			11,272,878		11,272,878		8,772,878
Shares available for grant (in shares)			2,552,097		2,552,097		1,296,793
Stock Incentive Plan | Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period (in years)					4 years
Stock-based compensation expense			$ 9,600,000	$ 900,000	$ 12,300,000	$ 2,700,000
Cumulative catch-up of compensation expense					$ 6,000,000

Stock-Based Compensation - Effe

Stock-Based Compensation - Effect of Stock-based Compensation Expense on Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 9,974	$ 933	$ 13,028	$ 2,887
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	370	138	722	374
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,358	298	2,639	1,023
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	3,067	179	3,502	532
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 5,179	$ 318	$ 6,165	$ 958

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Option Assumptions (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	0.00%
Expected term (in years)	0 days	6 years 3 months 18 days	6 years 3 months 18 days	6 years 3 months 18 days
Risk-free interest rate	0.00%
Expected dividends	0.00%	0.00%	0.00%	0.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	0.00%	45.60%	43.80%	46.40%
Risk-free interest rate	0.00%	2.90%	2.40%	2.50%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	0.00%	45.80%	44.50%	47.60%
Risk-free interest rate	0.00%	3.00%	2.50%	2.80%

Stock-Based Compensation - St_2

Stock-Based Compensation - Stock Option Activity (Details) - USD ($)	9 Months Ended
	Sep. 30, 2019
Time-Based Option Shares
Outstanding at January 1, 2019 (in shares)	7,237,417
Options granted (in shares)	1,198,121
Options exercised (in shares)	(301,427)
Options cancelled/forfeited (in shares)	(210,674)
Outstanding at June 30, 2019 (in shares)	7,923,437
Vested and expected to vest as of September 30, 2019	7,923,437
Vested and exercisable as of September 30, 2019	3,999,812
Weighted Average Exercise Price
Options outstanding, beginning balance, weighted-average exercise price, beginning balance (in USD per share)	$ 9.60
Options granted, weighted-average exercise price (in USD per share)	16
Options exercised, weighted-average exercise price (in USD per share)	7.22
Options cancelled/forfeited, weighted-average exercise price, (in USD per share)	10.51
Options outstanding, ending balance, weighted-average exercise price, ending balance (in USD per share)	10.64
Vested and expected to vest (in USD per share)	10.64
Vested and exercisable (in USD per share)	$ 8.92
Option shares outstanding, weighted average remaining contractual life	7 years 7 months 6 days
Vested and expected to vest, weighted average remaining contractual life	7 years 7 months 6 days
Vested and exercisable, weighted average remaining contractual life	6 years 4 months 24 days
Option shares outstanding, aggregate intrinsic value	$ 166,431,525
Option shares vested and expected to vest, aggregate intrinsic value	166,431,525
Option shares vested and exercisable, aggregate intrinsic value	$ 90,892,289

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Unit Activity (Details) - Restricted stock units	9 Months Ended
	Sep. 30, 2019$ / sharesshares
Restricted Stock Units
Unvested and outstanding, beginning balance (in shares) | shares	0
RSUs granted (in shares) | shares	257,278
Unvested and outstanding, ending balance (in shares) | shares	257,278
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Unvested and outstanding, beginning balance, grant date fair value (in USD per share) | $ / shares	$ 0
RSUs granted, grant date fair value, RSUs granted (in USD per share) | $ / shares	40.95
Unvested and outstanding, ending balance, grant date fair value (in USD per share) | $ / shares	$ 40.95

Stock-Based Compensation - Sch

Stock-Based Compensation - Schedule of the Purchase Right for the ESPP Option Assumptions (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	0.00%
Expected term (in months)	0 days	6 years 3 months 18 days	6 years 3 months 18 days	6 years 3 months 18 days
Risk-free interest rate	0.00%
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	44.00%
Expected term (in months)	5 months
Risk-free interest rate	2.00%
Expected dividends	$ 0

Income Taxes (Details)

Income Taxes (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Effective income tax rate	(0.10%)	(0.04%)	(0.09%)	0.29%

Deferred Revenue and Performa_2

Deferred Revenue and Performance Obligations - Remaining Performance Obligation (Details)	Sep. 30, 2019
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation (in percentage)	80.00%

Deferred Revenue and Performa_3

Deferred Revenue and Performance Obligations - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Product Information [Line Items]
Percentage of revenue recognized was included in deferred revenue (in percentage)	48.00%	36.00%	18.00%	13.00%
Revenue remaining performance obligation amount	$ 64		$ 64
Technology and professional services
Product Information [Line Items]
Service contract term			3 years
Allowed termination period			1 year
Notice required for termination			90 days

Related Parties (Details)

Related Parties (Details) - Board member - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Related Party Transaction [Line Items]
Revenue recognized from related party	$ 0.8	$ 1.2	$ 2.3	$ 3.1
Receivables from related party	1.1		1.1		$ 0.1
Acquisition-related consideration payable to related party	$ 2.4		$ 2.4		$ 3.3

Segments - Narrative (Details)

Segments - Narrative (Details)	9 Months Ended
	Sep. 30, 2019segment
Segment Reporting [Abstract]
Number of operating segments	2
Number of reportable segments	2

Segments - Scheduled of Segment

Segments - Scheduled of Segment Revenue (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue	[1]	$ 39,423	$ 32,868	$ 111,440	$ 76,490
Technology
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		21,160	18,283	61,393	38,459
Professional Services
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue		$ 18,263	$ 14,585	$ 50,047	$ 38,031
[1]	Includes amounts attributable to related party transactions. See Note 17 for further details.

Segments - Schedule of Segment

Segments - Schedule of Segment Adjusted Gross Profit (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Less Adjusted Gross Profit reconciling items:
Stock-based compensation		$ (9,974)	$ (933)	$ (13,028)	$ (2,887)
Less other reconciling items:
Sales and marketing	[1]	(14,721)	(13,771)	(35,579)	(32,496)
Research and development	[1]	(13,477)	(10,839)	(33,209)	(28,031)
General and administrative	[1]	(11,013)	(5,605)	(23,333)	(16,748)
Depreciation and amortization	[1]	(2,316)	(2,151)	(6,844)	(5,252)
Debt extinguishment costs		0	0	(1,670)	0
Interest and other expense, net		(659)	(374)	(2,924)	(1,389)
Net loss before income taxes		(21,395)	(16,869)	(45,787)	(48,551)
Operating segments
Adjusted Gross Profit
Gross profit		21,161	16,341	58,602	36,383
Operating segments | Technology
Adjusted Gross Profit
Gross profit		14,484	12,169	40,986	25,754
Operating segments | Professional Services
Adjusted Gross Profit
Gross profit		6,677	4,172	17,616	10,629
Segment reconciling items
Less Adjusted Gross Profit reconciling items:
Stock-based compensation		(370)	(138)	(722)	(374)
Tender offer payments deemed compensation		0	0	0	(312)
Post-acquisition restructuring costs		0	(332)	(108)	(332)
Less other reconciling items:
Sales and marketing		(14,721)	(13,771)	(35,579)	(32,496)
Research and development		(13,477)	(10,839)	(33,209)	(28,031)
General and administrative		(11,013)	(5,605)	(23,333)	(16,748)
Depreciation and amortization		(2,316)	(2,151)	(6,844)	(5,252)
Debt extinguishment costs		0	0	(1,670)	0
Interest and other expense, net		$ (659)	$ (374)	$ (2,924)	$ (1,389)
[1]	Includes amounts attributable to related party transactions. See Note 17 for further details.