BTRS (BTRS) 10-K 24 Mar 21 2020 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2020	Mar. 17, 2021	Jun. 30, 2020
Entity Listings [Line Items]
Entity Registrant Name	BTRS Holdings Inc.
Entity Central Index Key	0001774155
Current Fiscal Year End Date	--12-31
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Address, State or Province	NY
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Public Float			$ 232,051,775
Class 1 Common Stock [Member]
Entity Listings [Line Items]
Entity Common Stock, Shares Outstanding		149,178,593
Class 2 Common Stock [Member]
Entity Listings [Line Items]
Entity Common Stock, Shares Outstanding		7,251,307

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Current Assets
Cash	$ 1,017,402	$ 1,606,261
Prepaid income taxes	185,276	41,921
Prepaid expenses	72,533	102,712
Total Current Assets	1,275,211	1,750,894
Marketable securities held in Trust Account	252,292,955	251,865,941
TOTAL ASSETS	253,568,166	253,616,835
Current Liabilities
Accounts payable and accrued expenses	4,770,852	366,561
Total Current Liabilities	4,770,852	366,561
Deferred underwriting fee payable	7,970,375	7,970,375
Total Liabilities	12,741,227	8,336,936
Commitments and Contingencies (Note 6)
Stockholders' Equity
Preferred stock, $0.0001 par value; 1,000,000 shares authorized; none issued and outstanding	0	0
Additional paid-in capital	8,048,689	3,595,780
(Accumulated deficit) retained earnings	(3,049,473)	1,403,487
Total Stockholders' Equity	5,000,005	5,000,006
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	253,568,166	253,616,835
Class A Common Stock [Member]
Current Liabilities
Common stock subject to possible redemption, 23,363,827 and 23,861,949 shares at redemption value as of December 31, 2020 and 2019, respectively	235,826,934	240,279,893
Stockholders' Equity
Common stock	164	114
Class B Common Stock [Member]
Stockholders' Equity
Common stock	$ 625	$ 625

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Stockholders' Equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Class A Common Stock [Member]
LIABILITIES AND STOCKHOLDERS' EQUITY
Common stock, redemption (in shares)	23,363,827	23,861,949
Stockholders' Equity
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, shares issued (in shares)	1,636,173	1,138,051
Common stock, shares outstanding (in shares)	1,636,173	1,138,051
Class B Common Stock [Member]
Stockholders' Equity
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, shares issued (in shares)	6,250,000	6,250,000
Common stock, shares outstanding (in shares)	6,250,000	6,250,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	10 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2020
Formation and operating costs	$ 561,491	$ 5,359,676
Loss from operations	(561,491)	(5,359,676)
Other income:
Interest income on marketable securities held in Trust Account	2,338,057	909,361
Other income	2,338,057	909,361
(Loss) income before income taxes	1,776,566	(4,450,315)
Provision for income taxes	(373,079)	(2,645)
Net (loss) income	1,403,487	(4,452,960)
Common Stock Subject to Possible Redemption [Member]
Other income:
Interest income on marketable securities held in Trust Account	$ 2,231,675	$ 849,889
Weighted average shares outstanding, basic and diluted (in shares)	23,888,417	23,840,175
Basic and diluted net loss per common share (in dollars per share)	$ 0.07	$ 0.02
Non-Redeemable Class A and B Common Stock [Member]
Other income:
Net (loss) income	$ 1,403,487	$ (4,452,960)
Weighted average shares outstanding, basic and diluted (in shares)	6,908,855	7,409,825
Basic and diluted net loss per common share (in dollars per share)	$ (0.05)	$ (0.68)

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($)	Common Stock [Member]Class A Common Stock [Member]	Common Stock [Member]Class B Common Stock [Member]	Additional Paid-in Capital [Member]	(Accumulated Deficit)/ Retained Earnings [Member]	Total
Beginning balance at Feb. 27, 2019	$ 0	$ 0	$ 0	$ 0	$ 0
Beginning balance (in shares) at Feb. 27, 2019	0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class B common stock to Sponsor	$ 0	$ 647	24,353	0	25,000
Issuance of Class B common stock to Sponsor (in shares)	0	6,468,750
Sale of 25,000,000 Units, net of underwriting discount and offering expenses	$ 2,500	$ 0	236,894,412	0	236,896,912
Sale of 25,000,000 Units, net of underwriting discount and offering expenses (in shares)	25,000,000	0
Sale of 6,954,500 Private Placement Warrants	$ 0		6,954,500	0	6,954,500
Forfeiture of Founder Shares	$ 0	$ (22)	22	0	0
Forfeiture of Founder Shares (in shares)	0	(218,750)
Class A common stock subject to possible redemption	$ (2,386)	$ 0	(240,277,507)	0	(240,279,893)
Class A common stock subject to possible redemption (in shares)	(23,861,949)	0
Net (loss) income	$ 0	$ 0	0	1,403,487	1,403,487
Ending balance at Dec. 31, 2019	$ 114	$ 625	3,595,780	1,403,487	5,000,006
Ending balance (in shares) at Dec. 31, 2019	1,138,051	6,250,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Change in value of Class A common stock subject to possible redemption	$ 50	$ 0	4,452,909	0	4,452,959
Change in value of Class A common stock subject to possible redemption (in shares)	498,122	0
Net (loss) income	$ 0	$ 0	0	(4,452,960)	(4,452,960)
Ending balance at Dec. 31, 2020	$ 164	$ 625	$ 8,048,689	$ (3,049,473)	$ 5,000,005
Ending balance (in shares) at Dec. 31, 2020	1,636,173	6,250,000

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical)	Jun. 24, 2019shares
Initial Public Offering [Member]
Stockholders' Equity
Units issued (in shares)	25,000,000
Private Placement Warrants [Member]
Stockholders' Equity
Warrants issued (in shares)	6,954,500

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	10 Months Ended	12 Months Ended	22 Months Ended
	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2020
Cash Flows from Operating Activities:
Net (loss) income	$ 1,403,487	$ (4,452,960)
Adjustments to reconcile net (loss) income to net cash used in operating activities:
Interest earned on marketable securities held in Trust Account	(2,338,057)	(909,361)
Changes in operating assets and liabilities:
Prepaid expenses	(102,712)	30,179
Prepaid income taxes	(41,921)	(143,355)
Accounts payable and accrued expenses	366,561	4,404,291
Net cash used in operating activities	(712,642)	(1,071,206)
Cash Flows from Investing Activities:
Investment of cash in Trust Account	(250,000,000)	0
Cash withdrawn from Trust Account to pay franchise and income taxes	472,116	482,347	$ 954,463
Net cash provided by (used in) investing activities	(249,527,884)	482,347
Cash Flows from Financing Activities:
Proceeds from issuance of Class B common stock to Sponsor	25,000	0
Proceeds from sale of Units, net of underwriting discounts paid	245,445,500	0
Proceeds from sale of Private Placement Warrants	6,954,500	0
Proceeds from promissory notes - related party	175,000	0
Repayment of promissory notes - related party	(175,000)	0
Payment of offering costs	(578,213)	0
Net cash provided by financing activities	251,846,787	0
Net Change in Cash	1,606,261	(588,859)
Cash - Beginning	0	1,606,261	0
Cash - Ending	1,606,261	1,017,402	$ 1,017,402
Supplemental cash flow information:
Cash paid for income taxes	415,000	146,000
Non-cash investing and financing activities:
Initial classification of Class A common stock subject to redemption	238,875,410	0
Change in value of Class A common stock subject to possible redemption	1,404,483	(4,452,959)
Deferred underwriting fee payable	$ 7,970,375	$ 0

DESCRIPTION OF ORGANIZATION AND

DESCRIPTION OF ORGANIZATION AND BUSINESS OPERATIONS	12 Months Ended
	Dec. 31, 2020
DESCRIPTION OF ORGANIZATION AND BUSINESS OPERATIONS [Abstract]
DESCRIPTION OF ORGANIZATION AND BUSINESS OPERATIONS	NOTE 1—DESCRIPTION OF ORGANIZATION AND BUSINESS OPERATIONS BTRS Holdings Inc. (the “Company”), formerly known as South Mountain Merger Corp. (“South Mountain”) was incorporated in Delaware on February 28, 2019. The Company was formed for the purpose of effecting a merger, capital stock exchange, asset acquisition, stock purchase, reorganization or similar business combination with one or more businesses (the “Business Combination”). Business Combination On January 12, 2021, the Company consummated the previously announced Business Combination pursuant to the Agreement dated October 18, 2020 (as amended on December 13, 2020), between South Mountain, BT Merger Sub I, Inc., (“First Merger Sub”) a Delaware corporation and wholly owned subsidiary of South Mountain, BT Merger Sub II, LLC (“Second Merger Sub”), a Delaware limited liability company and wholly owned subsidiary of South Mountain, and Factor Systems, Inc. (“Billtrust”), a Delaware corporation, under the terms of which: (i) First Merger Sub merged with and into Billtrust (the “First Merger”), with Billtrust being the surviving company of the First Merger and (ii) immediately following the First Merger, Billtrust merged with and into Second Merger Sub, with Second Merger Sub being the surviving entity of the Second Merger. After giving effect to the Mergers, the Company owns, directly, all of the issued and outstanding equity interests of Billtrust, and the pre-Business Combination stockholders of Billtrust hold a portion of the combined Company’s Class A common stock and all of the combined Company’s Class C common stock. In connection with the closing of the Business Combination (the “Closing”), South Mountain changed its name to BTRS Holdings Inc. The Merger is accounted for as a reverse recapitalization in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Under this method of accounting, South Mountain will be treated as the “acquired” company for accounting purposes and the Business Combination will be treated as the equivalent of Billtrust issuing stock for the net assets of South Mountain, accompanied by a recapitalization. The net assets of South Mountain will be stated at historical cost, with no goodwill or other intangible assets recorded. As a result of the Agreement, Billtrust stockholders received aggregate consideration with a value equal to $1,189,502,229, which consists of (i) $90,061,329 in cash at Closing of the Business Combination, and (ii) $1,099,440,900 in South Mountain Class A Common Stock and South Mountain Class C Common Stock at Closing of the Business Combination, or 109,944,090 shares based on an assumed share price of $10 per share. In connection with the Business Combination, Billtrust stockholders will receive contingent consideration of up to 12,000,000 shares of South Mountain Class A Common Stock or South Mountain Class C Common Stock, as applicable (“Earnout Securities”), contingent upon achieving certain market share price milestones within a period of five years post Business Combination. In connection with the Business Combination, 1,875,000 shares of South Mountain Class A Common Stock previously issued to South Mountain LLC (the “Sponsor”) and its affiliates in exchange of the founder shares (“Sponsor Vesting Shares”) were placed in a lock-up and will be released from a lock-up upon achieving certain market share price milestones within a period of five years post-Closing. These shares will be forfeited if the set milestones are not reached. At the Closing, the Sponsor forfeited 1,250,000 shares of its South Mountain Class B Common Stock that it owned as of the Closing. Furthermore, in connection with the Business Combination, all of the Private Placement Warrants (see below) were forfeited, and in exchange, an additional 500,000 Sponsor Vesting Shares were issued which will vest based upon achieving certain market share price milestones within a period of five years post-Closing. These shares will be forfeited if the set milestones are not reached. During February 2021, the market share price milestones were reached and all 2,375,000 Sponsor Vesting Shares were earned, as were all the corresponding securities associated with the Earnout Securities. On October 18, 2020, a number of purchasers (each, a “Subscriber”) agreed to purchase from the Company an aggregate of 20,000,000 shares of South Mountain Class A Common Stock (the “PIPE Shares”), for a purchase price of $10.00 per share and an aggregate purchase price of $200,000,000, pursuant to separate subscription agreements (each, a “Subscription Agreement”) entered into effective as of October 18, 2020. Pursuant to the Subscription Agreements, the Company gave certain registration rights to the Subscribers with respect to the PIPE Shares. The sale of PIPE Shares was consummated concurrently with the Closing. Following the consummation of the Business Combination, all outstanding shares of South Mountain Class A Common Stock will be reclassified as shares of Class 1 Common Stock on a one-to-one basis and all outstanding shares of South Mountain Class C Common Stock will be reclassified as shares Class 2 common stock, par value $0.0001 per share (“Class 2 Common Stock”) on a one-to-one basis. As of the Closing Date and following the completion of the Business Combination, the Company had the following outstanding securities: • approximately 138,724,644 shares of Class 1 Common Stock, including 2,375,000 shares that are subject to the vesting and forfeiture provisions in the Share and Warrant Cancellation Agreement; • approximately 6,537,735 shares of Class 2 Common Stock; and • approximately 12,500,000 warrants, each exercisable for one share of Class 1 Common Stock at a price of $11.50 per share (the “Warrants”). Prior to the Business Combination All activity through December 31, 2020 related to the Company’s formation, the initial public offering (“Initial Public Offering”), which is described below, identifying a target company for a Business Combination, and activities in connection with the proposed acquisition of Billtrust. The registration statement for the Company’s Initial Public Offering was declared effective on June 19, 2019. On June 24, 2019, the Company consummated the Initial Public Offering of 25,000,000 units (the “Units” and, with respect to the shares of Class A common stock included in the Units sold, the “Public Shares”), which includes a partial exercise by the underwriter of the over-allotment option to purchase an additional 2,500,000 Units, at $10.00 per Unit, generating gross proceeds of $250,000,000, which is described in Note 3. Simultaneously with the closing of the Initial Public Offering, the Company consummated the sale of 6,954,500 warrants (the “Private Placement Warrants”) at a price of $1.00 per Private Placement Warrant in a private placement to the Sponsor, generating gross proceeds of $6,954,500, which is described in Note 4. Transaction costs amounted to $13,103,088, consisting of $4,554,500 of underwriting fees, $7,970,375 of deferred underwriting fees and $578,213 of other offering costs. Following the closing of the Initial Public Offering on June 24, 2019, an amount of $250,000,000 ($10.00 per Unit) from the net proceeds of the sale of the Units in the Initial Public Offering and the sale of the Private Placement Warrants was placed in a trust account (the “Trust Account”) which was invested in U.S. government securities, within the meaning set forth in Section 2(a)(16) of the Investment Company Act of 1940, as amended (the “Investment Company Act”), with a maturity of 185 days or less or in any open-ended investment company that holds itself out as a money market fund selected by the Company meeting the conditions of Rule 2a-7 of the Investment Company Act, as determined by the Company, until the Closing.

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2020
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	NOTE 2—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation The accompanying consolidated financial statements is presented in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and pursuant to the rules and regulations of the SEC. Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. Emerging Growth Company The Company is an “emerging growth company,” as defined in Section 2(a) of the Securities Act, as modified by the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”), and it may take advantage of certain exemptions from various reporting requirements that are applicable to other public companies that are not emerging growth companies including, but not limited to, not being required to comply with the independent registered public accounting firm attestation requirements of Section 404 of the Sarbanes-Oxley Act, reduced disclosure obligations regarding executive compensation in its periodic reports and proxy statements, and exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved. Further, Section 102(b)(1) of the JOBS Act exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies (that is, those that have not had a Securities Act registration statement declared effective or do not have a class of securities registered under the Exchange Act) are required to comply with the new or revised financial accounting standards. The JOBS Act provides that a company can elect to opt out of the extended transition period and comply with the requirements that apply to non-emerging growth companies but any such election to opt out is irrevocable. The Company has elected not to opt out of such extended transition period which means that when a standard is issued or revised and it has different application dates for public or private companies, the Company, as an emerging growth company, can adopt the new or revised standard at the time private companies adopt the new or revised standard. This may make comparison of the Company’s consolidated financial statements with another public company which is neither an emerging growth company nor an emerging growth company which has opted out of using the extended transition period difficult or impossible because of the potential differences in accounting standards used. Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management 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 consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Making estimates requires management to exercise significant judgment. It is at least reasonably possible that the estimate of the effect of a condition, situation or set of circumstances that existed at the date of the consolidated financial statements, which management considered in formulating its estimate, could change in the near term due to one or more future confirming events. Accordingly, the actual results could differ significantly from those estimates. Cash and Cash Equivalents The Company considers all short-term investments with an original maturity of three months or less when purchased to be cash equivalents. The Company did not have any cash equivalents as of December 31, 2020 and 2019. Marketable Securities Held in Trust Account At December 31, 2020 and 2019, substantially all of the assets held in the Trust Account were held in money market funds, which primarily invest in U.S. Treasury securities. The Company accounts for its securities held in the trust account in accordance with the guidance in Accounting Standards Codification ("ASC") Topic 320 "Debt and Equity Securities." These securities are classified as trading securities with unrealized gains/losses, if any, recognized through the statement of operations. Through December 31, 2020, the Company withdrew $954,463 of interest earned on the Trust Account to pay its franchise and income taxes, of which $482,347 was withdrawn during the year ended December 31, 2020. Class A Common Stock Subject to Possible Redemption The Company accounts for its Class A common stock subject to possible redemption in accordance with the guidance in ASC Topic 480 “Distinguishing Liabilities from Equity.” Shares of Class A common stock subject to mandatory redemption is classified as a liability instrument and is measured at fair value. Conditionally redeemable common stock (including common stock that features redemption rights that is either within the control of the holder or subject to redemption upon the occurrence of uncertain events not solely within the Company’s control) is classified as temporary equity. At all other times, common stock is classified as stockholders’ equity. The Company’s Class A common stock features certain redemption rights that are considered to be outside of the Company’s control and subject to occurrence of uncertain future events. Accordingly, Class A common stock subject to possible redemption is presented at redemption value as temporary equity, outside of the stockholders’ equity section of the Company’s balance sheets. Income Taxes The Company follows the asset and liability method of accounting for income taxes under ASC 740, “Income Taxes.” Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that included the enactment date. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized. ASC 740 prescribes a recognition threshold and a measurement attribute for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by taxing authorities. The Company recognizes accrued interest and penalties related to unrecognized tax benefits as income tax expense. There were no unrecognized tax benefits and no amounts accrued for interest and penalties as of December 31, 2020 and 2019. The Company is currently not aware of any issues under review that could result in significant payments, accruals or material deviation from its position. The Company may be subject to potential examination by federal, state and city taxing authorities in the areas of income taxes. These potential examinations may include questioning the timing and amount of deductions, the nexus of income among various tax jurisdictions and compliance with federal, state and city tax laws. The Company is subject to income tax examinations by major taxing authorities since inception. The Company’s management does not expect that the total amount of unrecognized tax benefits will materially change over the next twelve months. Net Earnings (Loss) Per Common Share Net Earnings (loss) per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding during the period. The Company has not considered the effect of the warrants sold in the Initial Public Offering and Private Placement to purchase an aggregate of 19,454,500 shares in the calculation of diluted loss per share, since the exercise of the warrants are contingent upon the occurrence of future events and the inclusion of such warrants would be anti-dilutive. The Company’s statement of operations includes a presentation of Earnings (loss) per share for common shares subject to possible redemption in a manner similar to the two-class method of Earnings (loss) per share. Net Earnings per common share, basic and diluted, for Common stock subject to possible redemption is calculated by dividing the proportionate share of income or loss on marketable securities held by the Trust Account, net of applicable franchise and income taxes, by the weighted average number of Common stock subject to possible redemption outstanding since original issuance. Net loss per share, basic and diluted, for non-redeemable common stock is calculated by dividing the net loss, adjusted for income or loss on marketable securities attributable to Common stock subject to possible redemption, by the weighted average number of non-redeemable common stock outstanding for the period. Non-redeemable common stock includes Founder Shares and non-redeemable shares of common stock as these shares do not have any redemption features. Non-redeemable common stock participates in the income or loss on marketable securities based on non-redeemable common stock shares’ proportionate interest. ​ Year Ended December 31, For the Period from February 28, 2019 (Inception) Through December 31, 2020 2019 Redeemable Class A Common Stock ​ Numerator: Earnings allocable to Redeemable Class A Common Stock ​ Interest Income $ 849,889 $ 2,231,675 Income Tax, Franchise Tax, and Regulatory Compliance Fees (286,939 ) (516,716 ) Net Earnings $ 562,950 $ 1,714,959 Denominator: Weighted Average Redeemable Class A Common Stock ​ Redeemable Class A Common Stock, Basic and Diluted 23,840,175 23,888,417 Earnings/Basic and Diluted Redeemable Class A Common Stock $ 0.02 $ 0.07 Non-Redeemable Class A and B Common Stock ​ Numerator: Net (Loss) Income minus Redeemable Net Earnings ​ Net (Loss) Income $ (4,452,960 ) $ 1,403,487 Less: Redeemable Net Earnings (562,950 ) (1,714,959 ) Non-Redeemable Net Loss $ (5,015,910 ) $ (311,472 ) Denominator: Weighted Average Non-Redeemable Class A and B Common Stock ​ Non-Redeemable Class A and B Common Stock, Basic and Diluted 7,409,825 6,908,855 Loss/Basic and Diluted Non-Redeemable Class A and B Common Stock $ (0.68 ) $ (0.05 ) Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist of a cash account in a financial institution, which, at times, may exceed the Federal Deposit Insurance Corporation coverage of $250,000. The Company has not experienced losses on this account and management believes the Company is not exposed to significant risks on such account. Fair Value of Financial Instruments The fair value of the Company’s assets and liabilities, which qualify as financial instruments under ASC 820, “Fair Value Measurement,” approximates the carrying amounts represented in the accompanying balance sheets, primarily due to their short-term nature. Recent Accounting Standards Management does not believe that any recently issued, but not yet effective, accounting standards, if currently adopted, would have a material effect on the Company’s consolidated financial statements.

INITIAL PUBLIC OFFERING

INITIAL PUBLIC OFFERING	12 Months Ended
	Dec. 31, 2020
INITIAL PUBLIC OFFERING [Abstract]
INITIAL PUBLIC OFFERING	NOTE 3—INITIAL PUBLIC OFFERING Pursuant to the Initial Public Offering, the Company sold 25,000,000 Units at a purchase price of $10.00 per Unit, which includes a partial exercise by the underwriter of its option to purchase an additional 2,500,000 Units at $10.00 per Unit. Each Unit consists of one share of Class A common stock and one-half of one warrant (“Public Warrant”). Each whole Public Warrant entitles the holder to purchase one share of Class A common stock at a price of $11.50 per share, subject to adjustment (see Note 7).

PRIVATE PLACEMENT

PRIVATE PLACEMENT	12 Months Ended
	Dec. 31, 2020
PRIVATE PLACEMENT [Abstract]
PRIVATE PLACEMENT	NOTE 4—PRIVATE PLACEMENT Simultaneously with the closing of the Initial Public Offering, the Sponsor purchased an aggregate of 6,954,500 Private Placement Warrants at a price of $1.00 per Private Placement Warrant, for an aggregate purchase price of $6,954,500. Each Private Placement Warrant is exercisable to purchase one share of Class A common stock at an exercise price of $11.50. The proceeds from the Private Placement Warrants were added to the proceeds from the Initial Public Offering held in the Trust Account.

RELATED PARTY TRANSACTIONS

RELATED PARTY TRANSACTIONS	12 Months Ended
	Dec. 31, 2020
RELATED PARTY TRANSACTIONS [Abstract]
RELATED PARTY TRANSACTIONS	NOTE 5—RELATED PARTY TRANSACTIONS Founder Shares In April 2019, the Sponsor purchased 5,750,000 shares (the “Founder Shares”) of the Company’s Class B common stock for an aggregate price of $25,000. On June 19, 2019, the Company effected a 1.125-for-1 stock split of its Class B common stock. As a result, the Sponsor held 6,468,750 Founder Shares, of which up to 218,750 shares were subject to forfeiture following the underwriter’s election to partially exercise its over-allotment option, so that the Sponsor would own, on an as-converted basis, 20% of the Company’s issued and outstanding shares after the Initial Public Offering (assuming the Sponsor did not purchase any Public Shares in the Initial Public Offering). The underwriters’ election to exercise their remaining over-allotment option expired unexercised on August 5, 2019 and, as a result, 218,750 Founder Shares were forfeited, resulting in 6,250,000 Founder Shares outstanding as of August 5, 2019. The Founder Shares were automatically converted into Class A common stock upon the consummation of the Business Combination on a one-for-one basis. The Sponsor has agreed, subject to certain limited exceptions, not to transfer, assign or sell any of its Founder Shares until the earlier to occur of: (i) one year after the completion of a Business Combination or (ii) the date on which the Company completes a liquidation, merger, capital stock exchange or other similar transaction that results in all of the Company’s stockholders having the right to exchange their shares of common stock for cash, securities or other property. Notwithstanding the foregoing, if the last sale price of the Class A common stock equals or exceeds $12.00 per share (as adjusted for stock splits, stock dividends, reorganizations, recapitalizations and the like) for any 20 trading days within any 30-trading day period commencing at least 150 days after a Business Combination, the Founder Shares will be released from the lock-up. Promissory Note—Related Party On April 19, 2019, the Company issued an unsecured promissory note to the Sponsor (the “Promissory Note”), pursuant to which the Sponsor agreed to loan the Company an aggregate of up to $300,000 to cover expenses related to the Initial Public Offering. The Promissory Note was non-interest bearing and payable on the earlier of December 31, 2019 or the completion of the Initial Public Offering. The borrowings outstanding under the Promissory Note of $175,000 were repaid upon the consummation of the Initial Public Offering on June 24, 2019. Administrative Support Agreement The Company entered into an agreement whereby, commencing on June 19, 2019, the Company will pay an affiliate of the Sponsor a total of $25,000 per month for office space, administrative and support services. Upon completion of the Business Combination or the Company’s liquidation, the Company will cease paying these monthly fees. For the year ended December 31, 2020 and for the period from February 28, 2019 (inception) through December 31, 2019, the Company incurred $300,000 and $150,000 in fees for these services, respectively, of which a total of $450,000 and $150,000 are included in accrued expenses in the accompanying balance sheets as of December 31, 2020 and 2019, respectively. Upon the Closing of the Business Combination, the Company ceased paying these monthly fees. Related Party Loans In order to finance transaction costs in connection with a Business Combination, the Sponsor, an affiliate of the Sponsor, or the Company’s officers and directors may, but none of them are obligated to, loan the Company funds from time to time or at any time, as may be required (“Working Capital Loans”). Each Working Capital Loan would be evidenced by a promissory note. The Working Capital Loans would either be paid upon consummation of a Business Combination, without interest, or, at the holder’s discretion, up to $1,500,000 of the Working Capital Loans may be converted into warrants at a price of $1.00 per warrant. The warrants would be identical to the Private Placement Warrants. In the event that a Business Combination does not close, the Company may use a portion of the proceeds held outside the Trust Account to repay the Working Capital Loans, but no proceeds held in the Trust Account would be used to repay the Working Capital Loans.

COMMITMENTS

COMMITMENTS	12 Months Ended
	Dec. 31, 2020
COMMITMENTS [Abstract]
COMMITMENTS	NOTE 6—COMMITMENTS Registration Rights Pursuant to a registration rights agreement entered into on June 19, 2019, the holders of the Founder Shares, Private Placement Warrants and warrants issued upon conversion of Working Capital Loans (and any shares of common stock issuable upon the exercise of the Private Placement Warrants or warrants issued upon conversion of the Working Capital Loans) will be entitled to registration rights pursuant to a registration rights agreement to be signed prior to or on the effective date of the Initial Public Offering requiring the Company to register such securities for resale (in the case of the Founder Shares, only after conversion into shares of Class A common stock). These holders of these securities will be entitled to make up to three demands, excluding short form registration demands, that the Company register such securities. In addition, the holders have certain “piggy-back” registration rights with respect to registration statements filed subsequent to the completion of a Business Combination and rights to require the Company to register for resale such securities pursuant to Rule 415 under the Securities Act. The Company will bear the expenses incurred in connection with the filing of any such registration statements. Sale of Units to Related Party A fund managed by an affiliate of the Sponsor purchased 2,227,500 Units in the Initial Public Offering at the Initial Public Offering price. The underwriter did not receive any underwriting discount or commissions on the Units purchased by such fund. Underwriting Agreement The underwriter was paid a cash underwriting discount of 2.0% of the gross proceeds from the Units sold in the Initial Public Offering, after deducting the proceeds received from the fund managed by an affiliate of the Sponsor, or $4,554,500 in the aggregate. In addition, the underwriter was entitled to a deferred fee of 3.5% of the gross proceeds from the Units sold in the Initial Public Offering, or $7,970,375. The deferred fee was paid upon the closing of the Business Combination from the amounts held in the Trust Account. Advisory and Other Services Agreements During the fourth quarter of 2020, the Company entered into an agreement with a firm to provide financial advisory and investment banking services to the Company in connection with the contemplated Business Combination based on which Additionally, during the fourth quarter of 2020, the Company entered into an agreement with Citigroup Global Markets Inc., as the Company's placement agent and exclusive capital markets advisor in connection with the Company's business combination based on which placement fee would be payable in cash upon consummation of the Business Combination, calculated as 4% of gross proceeds of securities sold in connection with the Business Combination. The above success-based advisory and banking fees were paid upon completion of the Business Combination, which occurred in January 2021.

STOCKHOLDERS' EQUITY

STOCKHOLDERS' EQUITY	12 Months Ended
	Dec. 31, 2020
STOCKHOLDERS' EQUITY [Abstract]
STOCKHOLDERS' EQUITY	NOTE 7—STOCKHOLDERS’ EQUITY Preferred Stock Class A Common Stock Class B Common Stock Holders of Class B common stock will have the right to elect all of the Company’s directors prior to the consummation of a Business Combination. On any other matter submitted to a vote of the Company’s stockholders, holders of Class A common stock and Class B common stock will vote together as a single class on all other matters submitted to a vote of stockholders, except as required by law. These provisions of the Company’s Amended and Restated Certificate of Incorporation may only be amended if approved by a majority of at least 90% of the Company’s common stock voting at a stockholder meeting. Class C Common Stock The Company is authorized to issue 27,000,000 shares of Class C common stock with a par value of $0.0001 per share. At December 31, 2020 and 2019, there were no shares of Class C common stock issued and outstanding. Holders of South Mountain Class C Common Stock will not be entitled to vote on any matters to be voted on by stockholders (except for a limited number of corporate actions on which such nonvoting shares are entitled to vote under the Delaware General Corporation Law). Except as expressly provided in the prior sentence with respect to voting, the Class C common stock and the Class A common stock will be identical in all respects and will be pari passu with one another, and share ratably on a per share basis in respect of, the payment of dividends and the distribution of assets on the liquidation, dissolution or winding up of the Company. Warrants Redemptions of Warrants for Cash • in whole and not in part; • at a price of $0.01 per warrant; • upon a minimum of 30 days’ prior written notice of redemption; and • if, and only if, the reported last sale price of the Company’s Class A common stock equals or exceeds $18.00 per share for any 20 trading days within a 30-trading day period ending on the third trading day prior to the date on which the Company sends the notice of redemption to the warrant holders. If and when the warrants become redeemable by the Company, the Company may exercise its redemption right even if it is unable to register or qualify the underlying securities for sale under all applicable state securities laws.

INCOME TAX

INCOME TAX	12 Months Ended
	Dec. 31, 2020
INCOME TAX [Abstract]
INCOME TAX	NOTE 8 — INCOME TAX The income tax provision for the year ended December 31, 2020 and for the period from February 28, 2019 (inception) through December 31, 2019 consists of the following: December 31, 2020 December 31, 2019 Federal Current $ 2,645 $ 373,079 Deferred — — State and Local Current — — Deferred — — Change in valuation allowance — — Income tax provision $ 2,645 $ 373,079 The Company did not have any net deferred tax assets or liabilities at December 31, 2020 and 2019. As of December 31, 2020 and 2019, the Company did not have any of U.S. federal and state net operating loss carryovers available to offset future taxable income. In assessing the realization of the deferred tax assets, management considers whether it is more likely than not that some portion of all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which temporary differences representing net future deductible amounts become deductible. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income and tax planning strategies in making this assessment. A reconciliation of the federal income tax rate to the Company’s effective tax rate at December 31, 2020 and 2019 is as follows: December 31, 2020 December 31, 2019 Statutory federal income tax rate 21.0 % 21.0 % State taxes, net of federal tax benefit 0.0 % 0.0 % Business Combinations (21.1 )% 0.0 % Valuation allowance 0.0 % 0.0 % Income tax provision (0.1 )% 21.0 % The Company files income tax returns in the U.S. federal jurisdiction and is subject to examination by the various taxing authorities. The Company's tax returns since inception remain open to examination by the taxing authorities.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	12 Months Ended
	Dec. 31, 2020
FAIR VALUE MEASUREMENTS [Abstract]
FAIR VALUE MEASUREMENTS	NOTE 9—FAIR VALUE MEASUREMENTS The Company follows the guidance in ASC 820 for its financial assets and liabilities that are re-measured and reported at fair value at each reporting period, and non-financial assets and liabilities that are re-measured and reported at fair value at least annually. The fair value of the Company’s financial assets and liabilities reflects management’s estimate of amounts that the Company would have received in connection with the sale of the assets or paid in connection with the transfer of the liabilities in an orderly transaction between market participants at the measurement date. In connection with measuring the fair value of its assets and liabilities, the Company seeks to maximize the use of observable inputs (market data obtained from independent sources) and to minimize the use of unobservable inputs (internal assumptions about how market participants would price assets and liabilities). The following fair value hierarchy is used to classify assets and liabilities based on the observable inputs and unobservable inputs used in order to value the assets and liabilities: Level 1: Quoted prices in active markets for identical assets or liabilities. An active market for an asset or liability is a market in which transactions for the asset or liability occur with sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2: Observable inputs other than Level 1 inputs. Examples of Level 2 inputs include quoted prices in active markets for similar assets or liabilities and quoted prices for identical assets or liabilities in markets that are not active. Level 3: Unobservable inputs based on the Company’s assessment of the assumptions that market participants would use in pricing the asset or liability. The following table presents information about the Company’s assets that are measured at fair value on a recurring basis at December 31, 2020 and 2019, and indicates the fair value hierarchy of the valuation inputs the Company utilized to determine such fair value: Description Level December 31, 2020 December 31, 2019 Assets: Marketable securities held in Trust Account 1 $ 252,292,955 $ 251,865,941

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	12 Months Ended
	Dec. 31, 2020
SUBSEQUENT EVENTS [Abstract]
SUBSEQUENT EVENTS	NOTE 10—SUBSEQUENT EVENTS The Company evaluated subsequent events and transactions that occurred after the balance sheet date up to the date that the consolidated financial statements were issued. Based upon this review, other than as described below, the Company did not identify any subsequent events that would have required adjustment or disclosure in the consolidated financial statements. As described in Note 1, the Company completed the Business Combination on January 12, 2021.

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2020
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES [Abstract]
Basis of Presentation	Basis of Presentation The accompanying consolidated financial statements is presented in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and pursuant to the rules and regulations of the SEC.
Principles of Consolidation	Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management 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 consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Making estimates requires management to exercise significant judgment. It is at least reasonably possible that the estimate of the effect of a condition, situation or set of circumstances that existed at the date of the consolidated financial statements, which management considered in formulating its estimate, could change in the near term due to one or more future confirming events. Accordingly, the actual results could differ significantly from those estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all short-term investments with an original maturity of three months or less when purchased to be cash equivalents. The Company did not have any cash equivalents as of December 31, 2020 and 2019.
Marketable Securities Held in Trust Account	Marketable Securities Held in Trust Account At December 31, 2020 and 2019, substantially all of the assets held in the Trust Account were held in money market funds, which primarily invest in U.S. Treasury securities. The Company accounts for its securities held in the trust account in accordance with the guidance in Accounting Standards Codification ("ASC") Topic 320 "Debt and Equity Securities." These securities are classified as trading securities with unrealized gains/losses, if any, recognized through the statement of operations. Through December 31, 2020, the Company withdrew $954,463 of interest earned on the Trust Account to pay its franchise and income taxes, of which $482,347 was withdrawn during the year ended December 31, 2020.
Class A Common Stock Subject to Possible Redemption	Class A Common Stock Subject to Possible Redemption The Company accounts for its Class A common stock subject to possible redemption in accordance with the guidance in ASC Topic 480 “Distinguishing Liabilities from Equity.” Shares of Class A common stock subject to mandatory redemption is classified as a liability instrument and is measured at fair value. Conditionally redeemable common stock (including common stock that features redemption rights that is either within the control of the holder or subject to redemption upon the occurrence of uncertain events not solely within the Company’s control) is classified as temporary equity. At all other times, common stock is classified as stockholders’ equity. The Company’s Class A common stock features certain redemption rights that are considered to be outside of the Company’s control and subject to occurrence of uncertain future events. Accordingly, Class A common stock subject to possible redemption is presented at redemption value as temporary equity, outside of the stockholders’ equity section of the Company’s balance sheets.
Income Taxes	Income Taxes The Company follows the asset and liability method of accounting for income taxes under ASC 740, “Income Taxes.” Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that included the enactment date. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized. ASC 740 prescribes a recognition threshold and a measurement attribute for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by taxing authorities. The Company recognizes accrued interest and penalties related to unrecognized tax benefits as income tax expense. There were no unrecognized tax benefits and no amounts accrued for interest and penalties as of December 31, 2020 and 2019. The Company is currently not aware of any issues under review that could result in significant payments, accruals or material deviation from its position. The Company may be subject to potential examination by federal, state and city taxing authorities in the areas of income taxes. These potential examinations may include questioning the timing and amount of deductions, the nexus of income among various tax jurisdictions and compliance with federal, state and city tax laws. The Company is subject to income tax examinations by major taxing authorities since inception. The Company’s management does not expect that the total amount of unrecognized tax benefits will materially change over the next twelve months.
Net Earnings (Loss) per Common Share	Net Earnings (Loss) Per Common Share Net Earnings (loss) per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding during the period. The Company has not considered the effect of the warrants sold in the Initial Public Offering and Private Placement to purchase an aggregate of 19,454,500 shares in the calculation of diluted loss per share, since the exercise of the warrants are contingent upon the occurrence of future events and the inclusion of such warrants would be anti-dilutive. The Company’s statement of operations includes a presentation of Earnings (loss) per share for common shares subject to possible redemption in a manner similar to the two-class method of Earnings (loss) per share. Net Earnings per common share, basic and diluted, for Common stock subject to possible redemption is calculated by dividing the proportionate share of income or loss on marketable securities held by the Trust Account, net of applicable franchise and income taxes, by the weighted average number of Common stock subject to possible redemption outstanding since original issuance. Net loss per share, basic and diluted, for non-redeemable common stock is calculated by dividing the net loss, adjusted for income or loss on marketable securities attributable to Common stock subject to possible redemption, by the weighted average number of non-redeemable common stock outstanding for the period. Non-redeemable common stock includes Founder Shares and non-redeemable shares of common stock as these shares do not have any redemption features. Non-redeemable common stock participates in the income or loss on marketable securities based on non-redeemable common stock shares’ proportionate interest. ​ Year Ended December 31, For the Period from February 28, 2019 (Inception) Through December 31, 2020 2019 Redeemable Class A Common Stock ​ Numerator: Earnings allocable to Redeemable Class A Common Stock ​ Interest Income $ 849,889 $ 2,231,675 Income Tax, Franchise Tax, and Regulatory Compliance Fees (286,939 ) (516,716 ) Net Earnings $ 562,950 $ 1,714,959 Denominator: Weighted Average Redeemable Class A Common Stock ​ Redeemable Class A Common Stock, Basic and Diluted 23,840,175 23,888,417 Earnings/Basic and Diluted Redeemable Class A Common Stock $ 0.02 $ 0.07 Non-Redeemable Class A and B Common Stock ​ Numerator: Net (Loss) Income minus Redeemable Net Earnings ​ Net (Loss) Income $ (4,452,960 ) $ 1,403,487 Less: Redeemable Net Earnings (562,950 ) (1,714,959 ) Non-Redeemable Net Loss $ (5,015,910 ) $ (311,472 ) Denominator: Weighted Average Non-Redeemable Class A and B Common Stock ​ Non-Redeemable Class A and B Common Stock, Basic and Diluted 7,409,825 6,908,855 Loss/Basic and Diluted Non-Redeemable Class A and B Common Stock $ (0.68 ) $ (0.05 )
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist of a cash account in a financial institution, which, at times, may exceed the Federal Deposit Insurance Corporation coverage of $250,000. The Company has not experienced losses on this account and management believes the Company is not exposed to significant risks on such account.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The fair value of the Company’s assets and liabilities, which qualify as financial instruments under ASC 820, “Fair Value Measurement,” approximates the carrying amounts represented in the accompanying balance sheets, primarily due to their short-term nature.
Recent Accounting Standards	Recent Accounting Standards Management does not believe that any recently issued, but not yet effective, accounting standards, if currently adopted, would have a material effect on the Company’s consolidated financial statements.

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	Dec. 31, 2020
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES [Abstract]
Basic and Diluted Loss Per Common Share	Non-redeemable common stock includes Founder Shares and non-redeemable shares of common stock as these shares do not have any redemption features. Non-redeemable common stock participates in the income or loss on marketable securities based on non-redeemable common stock shares’ proportionate interest. ​ Year Ended December 31, For the Period from February 28, 2019 (Inception) Through December 31, 2020 2019 Redeemable Class A Common Stock ​ Numerator: Earnings allocable to Redeemable Class A Common Stock ​ Interest Income $ 849,889 $ 2,231,675 Income Tax, Franchise Tax, and Regulatory Compliance Fees (286,939 ) (516,716 ) Net Earnings $ 562,950 $ 1,714,959 Denominator: Weighted Average Redeemable Class A Common Stock ​ Redeemable Class A Common Stock, Basic and Diluted 23,840,175 23,888,417 Earnings/Basic and Diluted Redeemable Class A Common Stock $ 0.02 $ 0.07 Non-Redeemable Class A and B Common Stock ​ Numerator: Net (Loss) Income minus Redeemable Net Earnings ​ Net (Loss) Income $ (4,452,960 ) $ 1,403,487 Less: Redeemable Net Earnings (562,950 ) (1,714,959 ) Non-Redeemable Net Loss $ (5,015,910 ) $ (311,472 ) Denominator: Weighted Average Non-Redeemable Class A and B Common Stock ​ Non-Redeemable Class A and B Common Stock, Basic and Diluted 7,409,825 6,908,855 Loss/Basic and Diluted Non-Redeemable Class A and B Common Stock $ (0.68 ) $ (0.05 )

INCOME TAX (Tables)

INCOME TAX (Tables)	12 Months Ended
	Dec. 31, 2020
INCOME TAX [Abstract]
Income Tax Provision During Period	The income tax provision for the year ended December 31, 2020 and for the period from February 28, 2019 (inception) through December 31, 2019 consists of the following: December 31, 2020 December 31, 2019 Federal Current $ 2,645 $ 373,079 Deferred — — State and Local Current — — Deferred — — Change in valuation allowance — — Income tax provision $ 2,645 $ 373,079
Reconciliation of Federal Income Tax Rate	A reconciliation of the federal income tax rate to the Company’s effective tax rate at December 31, 2020 and 2019 is as follows: December 31, 2020 December 31, 2019 Statutory federal income tax rate 21.0 % 21.0 % State taxes, net of federal tax benefit 0.0 % 0.0 % Business Combinations (21.1 )% 0.0 % Valuation allowance 0.0 % 0.0 % Income tax provision (0.1 )% 21.0 %

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	12 Months Ended
	Dec. 31, 2020
FAIR VALUE MEASUREMENTS [Abstract]
Assets Measured on Recurring Basis	The following table presents information about the Company’s assets that are measured at fair value on a recurring basis at December 31, 2020 and 2019, and indicates the fair value hierarchy of the valuation inputs the Company utilized to determine such fair value: Description Level December 31, 2020 December 31, 2019 Assets: Marketable securities held in Trust Account 1 $ 252,292,955 $ 251,865,941

DESCRIPTION OF ORGANIZATION A_2

DESCRIPTION OF ORGANIZATION AND BUSINESS OPERATIONS, Business Combination (Details) - USD ($)	Jan. 12, 2021	Feb. 28, 2021	Dec. 31, 2020	Oct. 18, 2020	Dec. 31, 2019	Aug. 05, 2019
Business Combination [Abstract]
Exercise price of warrant (in dollars per share)			$ 11.50
Class A Common Stock [Member]
Business Combination [Abstract]
Common Stock, Value, Subscriptions				$ 200,000,000
Common stock subscriptions (in dollars per share)				$ 10
Common stock subscriptions (in shares)				20,000,000
Common stock, par value (in dollars per share)			$ 0.0001		$ 0.0001
Common stock, shares outstanding (in shares)			1,636,173		1,138,051
Class B Common Stock [Member]
Business Combination [Abstract]
Number of shares forfeited (in shares)						218,750
Common stock, par value (in dollars per share)			$ 0.0001		$ 0.0001
Common stock, shares outstanding (in shares)			6,250,000		6,250,000
Class C Common Stock [Member]
Business Combination [Abstract]
Common stock, par value (in dollars per share)			$ 0.0001		$ 0.0001
Common stock, shares outstanding (in shares)			0		0
Sponsor [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Vesting share earned (in shares)		2,375,000
Sponsor [Member] | Class A Common Stock [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Contingent consideration (in shares)	$ 1,875,000
Contingent period post business combination for achieving certain market share price milestones	5 years
Nonvested shares issued (in shares)	500,000
Vesting period	5 years
Sponsor [Member] | Class B Common Stock [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Number of shares forfeited (in shares)	1,250,000
Billtrust [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Aggregate consideration	$ 1,189,502,229
Consideration in cash	$ 90,061,329
Billtrust [Member] | Warrant [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Number of rights reclassified into new shares (in shares)	1
Exercise price of warrant (in dollars per share)	$ 11.50
Billtrust [Member] | Class A Common Stock and Class C Common Stock [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Equity consideration	$ 1,099,440,900
Equity consideration in shares (in shares)	109,944,090
Share price (in dollars per share)	$ 10
Billtrust [Member] | Class A Common Stock and Class C Common Stock [Member] | Maximum [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Contingent consideration (in shares)	$ 12,000,000
Contingent period post business combination for achieving certain market share price milestones	5 years
Billtrust [Member] | Class A Common Stock [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Number of new shares called by each right (in shares)	1
Billtrust [Member] | Class C Common Stock [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Number of rights reclassified into new shares (in shares)	1
Billtrust [Member] | Class 1 Common Stock [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Common stock, shares outstanding (in shares)	138,724,644
Common stock, shares subject to vesting and forfeiture (in shares)	2,375,000
Warrants outstanding (in shares)	12,500,000
Billtrust [Member] | Class 2 Common Stock [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Number of new shares called by each right (in shares)	1
Common stock, par value (in dollars per share)	$ 0.0001
Common stock, shares outstanding (in shares)	6,537,735
South Mountain [Member] | Class A Common Stock [Member] | Subsequent Event [Member]
Business Combination [Abstract]
Number of rights reclassified into new shares (in shares)	1

DESCRIPTION OF ORGANIZATION A_3

DESCRIPTION OF ORGANIZATION AND BUSINESS OPERATIONS, Business Prior to the Business Combination (Details) - USD ($)	Jun. 24, 2019	Dec. 31, 2020	Dec. 31, 2019
Business Prior to the Business Combination [Abstract]
Gross proceeds from initial public offering	$ 250,000,000
Transaction costs	13,103,088
Underwriting fees	4,554,500
Deferred underwriting fees	7,970,375
Other costs	578,213
Net proceeds deposited in trust account	$ 250,000,000	$ 252,292,955	$ 251,865,941
Private Placement Warrants [Member]
Business Prior to the Business Combination [Abstract]
Share price (in dollars per share)	$ 1
Warrants issued (in shares)	6,954,500
Gross proceeds from issuance of warrants	$ 6,954,500
Initial Public Offering [Member]
Business Prior to the Business Combination [Abstract]
Units issued (in shares)	25,000,000
Initial Public Offering [Member] | Public Shares [Member]
Business Prior to the Business Combination [Abstract]
Units issued (in shares)	25,000,000
Share price (in dollars per share)	$ 10
Redemption price (in dollars per share)	$ 10
Over-Allotment Option [Member] | Public Shares [Member]
Business Prior to the Business Combination [Abstract]
Units issued (in shares)	2,500,000
Share price (in dollars per share)	$ 10

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($)	10 Months Ended	12 Months Ended	22 Months Ended
	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2020
Cash and Cash Equivalents [Abstract]
Cash equivalents	$ 0	$ 0	$ 0
Marketable Securities Held in Trust Account [Abstract]
Interest withdrawn from trust account to pay its franchise and income taxes	472,116	482,347	954,463
Income Taxes [Abstract]
Unrecognized tax benefits	0	0	0
Accrued interest and penalties	0	0	$ 0
Numerator: Net (Loss) Income minus Redeemable Net Earnings [Abstract]
Net (loss) income	1,403,487	(4,452,960)
Investment Income, Interest	2,338,057	$ 909,361
Class A Common Stock [Member]
Net income (loss) per common share [Abstract]
Antidilutive securities excluded from computation of earnings per share (in shares)		19,454,500
Redeemable Class A Common Stock [Member]
Numerator: Net (Loss) Income minus Redeemable Net Earnings [Abstract]
Investment Income, Interest	2,231,675	$ 849,889
Income Taxes and Regulatory Compliance Fees	(516,716)	(286,939)
Net Earnings	$ 1,714,959	$ 562,950
Denominator: Weighted Average Non-Redeemable Class A and B Common Stock [Abstract]
Weighted average shares, basic and diluted (in shares)	23,888,417	23,840,175
Basic and diluted net earnings/loss per share (in dollars per share)	$ 0.07	$ 0.02
Non-Redeemable Class A and B Common Stock [Member]
Numerator: Net (Loss) Income minus Redeemable Net Earnings [Abstract]
Net (loss) income	$ 1,403,487	$ (4,452,960)
Net Earnings	(1,714,959)	(562,950)
Non-Redeemable Net Loss	$ (311,472)	$ (5,015,910)
Denominator: Weighted Average Non-Redeemable Class A and B Common Stock [Abstract]
Weighted average shares, basic and diluted (in shares)	6,908,855	7,409,825
Basic and diluted net earnings/loss per share (in dollars per share)	$ (0.05)	$ (0.68)

INITIAL PUBLIC OFFERING (Detail

INITIAL PUBLIC OFFERING (Details) - $ / shares	Jun. 24, 2019	Dec. 31, 2020
Initial Public Offering [Abstract]
Exercise price of warrant (in dollars per share)		$ 11.50
Initial Public Offering [Member]
Initial Public Offering [Abstract]
Units issued (in shares)	25,000,000
Initial Public Offering [Member] | Public Shares [Member]
Initial Public Offering [Abstract]
Units issued (in shares)	25,000,000
Unit price (in dollars per share)	$ 10
Initial Public Offering [Member] | Public Warrant [Member]
Initial Public Offering [Abstract]
Number of securities called by each unit (in shares)	0.5
Exercise price of warrant (in dollars per share)	$ 11.50
Initial Public Offering [Member] | Class A Common Stock [Member]
Initial Public Offering [Abstract]
Number of securities called by each unit (in shares)	1
Number of securities called by each warrant (in shares)	1
Over-Allotment Option [Member] | Public Shares [Member]
Initial Public Offering [Abstract]
Units issued (in shares)	2,500,000
Unit price (in dollars per share)	$ 10

PRIVATE PLACEMENT (Details)

PRIVATE PLACEMENT (Details) - USD ($)	Jun. 24, 2019	Dec. 31, 2020
Private Placement Warrants [Abstract]
Warrants exercise price (in dollars per share)		$ 11.50
Private Placement Warrants [Member]
Private Placement Warrants [Abstract]
Warrants issued (in shares)	6,954,500
Share price (in dollars per share)	$ 1
Gross proceeds from issuance of warrants	$ 6,954,500
Class A Common Stock [Member] | Private Placement Warrants [Member]
Private Placement Warrants [Abstract]
Number of securities called by each warrant (in shares)	1
Warrants exercise price (in dollars per share)	$ 11.50

RELATED PARTY TRANSACTIONS, Fou

RELATED PARTY TRANSACTIONS, Founder Shares (Details)	Jun. 19, 2019shares	Apr. 30, 2019USD ($)shares	Dec. 31, 2019USD ($)	Dec. 31, 2020USD ($)$ / shares	Aug. 05, 2019shares
Founder Shares [Abstract]
Proceeds from issuance of Class B common stock to Sponsor | $			$ 25,000	$ 0
Number of trading days				20 days
Trading day threshold period				30 days
Class A Common Stock [Member]
Founder Shares [Abstract]
Share price (in dollars per share) | $ / shares				$ 18
Class B Common Stock [Member]
Founder Shares [Abstract]
Number of shares outstanding (in shares)					6,250,000
Number of shares forfeited (in shares)					218,750
Sponsor [Member] | Class A Common Stock [Member]
Founder Shares [Abstract]
Stock conversion basis at time of business combination				1
Number of trading days				20 days
Trading day threshold period				30 days
Sponsor [Member] | Class A Common Stock [Member] | Minimum [Member]
Founder Shares [Abstract]
Share price (in dollars per share) | $ / shares				$ 12
Threshold period after initial Business Combination				150 days
Sponsor [Member] | Class B Common Stock [Member]
Founder Shares [Abstract]
Shares issued (in shares)		5,750,000
Proceeds from issuance of Class B common stock to Sponsor | $		$ 25,000
Stock split ratio	1.125
Number of shares outstanding (in shares)	6,468,750
Ownership interest, as converted percentage	20.00%
Sponsor [Member] | Class B Common Stock [Member] | Maximum [Member]
Founder Shares [Abstract]
Number of shares subject to forfeiture (in shares)	218,750

RELATED PARTY TRANSACTIONS, Pro

RELATED PARTY TRANSACTIONS, Promissory Note-Related Party, Administrative Support Agreement, Related Party Loans (Details) - USD ($)	Jun. 24, 2019	Jun. 19, 2019	Apr. 19, 2019	Dec. 31, 2019	Dec. 31, 2020
Related Party Transactions [Abstract]
Repayment of debt to related party				$ 175,000	$ 0
Sponsor [Member] | Promissory Note [Member]
Related Party Transactions [Abstract]
Related party transaction			$ 300,000
Repayment of debt to related party	$ 175,000
Sponsor [Member] | Administrative Support Agreement [Member]
Related Party Transactions [Abstract]
Related party transaction		$ 25,000
Related party expense				150,000	300,000
Sponsor [Member] | Administrative Support Agreement [Member] | Accrued Expenses [Member]
Related Party Transactions [Abstract]
Related party fees payable				$ 150,000	$ 450,000
Sponsor or an Affiliate of the Sponsor, or Certain of the Company's Officers and Directors [Member] | Working Capital Loans [Member]
Related Party Transactions [Abstract]
Unit price (in dollars per share)					$ 1
Sponsor or an Affiliate of the Sponsor, or Certain of the Company's Officers and Directors [Member] | Working Capital Loans [Member] | Maximum [Member]
Related Party Transactions [Abstract]
Related party transaction					$ 1,500,000

COMMITMENTS (Details)

COMMITMENTS (Details) - USD ($)	Jun. 24, 2019	Dec. 31, 2020
Underwriting Agreement [Abstract]
Cash underwriting discount	2.00%
Underwriting expense	$ 4,554,500
Deferred underwriting discount	3.50%
Deferred underwriting fees	$ 7,970,375
Advisory and Other Services Agreements [Abstract]
Business combination success fee		$ 1,100,000
Percentage of gross proceeds securities sold for business combination		4.00%
Initial Public Offering [Member]
Underwriting Agreement [Abstract]
Units issued (in shares)	25,000,000
Affiliate of Sponsor [Member] | Initial Public Offering [Member]
Underwriting Agreement [Abstract]
Units issued (in shares)	2,227,500

STOCKHOLDERS' EQUITY, Preferred

STOCKHOLDERS' EQUITY, Preferred Stock and Common Stock (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Stockholders' Equity [Abstract]
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Minimum [Member]
Stockholders' Equity [Abstract]
Voting percentage of common stock	90.00%
Class A Common Stock [Member]
Stockholders' Equity [Abstract]
Common stock, shares authorized (in shares)	200,000,000	200,000,000
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares issued (in shares)	1,636,173	1,138,051
Common stock, shares outstanding (in shares)	1,636,173	1,138,051
Voting right per share	One vote
Common stock subject to possible redemption (in shares)	23,363,827	23,861,949
Class B Common Stock [Member]
Stockholders' Equity [Abstract]
Common stock, shares authorized (in shares)	20,000,000	20,000,000
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares issued (in shares)	6,250,000	6,250,000
Common stock, shares outstanding (in shares)	6,250,000	6,250,000
Voting right per share	One vote
Class C Common Stock [Member]
Stockholders' Equity [Abstract]
Common stock, shares authorized (in shares)	27,000,000	27,000,000
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares issued (in shares)	0	0
Common stock, shares outstanding (in shares)	0	0

STOCKHOLDERS' EQUITY, Warrants

STOCKHOLDERS' EQUITY, Warrants (Details)	12 Months Ended
	Dec. 31, 2020$ / shares
Warrants [Abstract]
Warrants exercise price (in dollars per share)	$ 11.50
Number of days to file registration statement	15 days
Period for registration statement to become effective	60 days
Expiration period of warrants	5 years
Warrant redemption price (in dollars per share)	$ 0.01
Notice period to redeem warrants	30 days
Number of trading days	20 days
Trading day threshold period	30 days
Minimum [Member]
Warrants [Abstract]
Period for warrants to become exercisable	30 days
Maximum [Member]
Warrants [Abstract]
Period for warrants to become exercisable	12 months
Class A Common Stock [Member]
Warrants [Abstract]
Share price (in dollars per share)	$ 18

INCOME TAX (Details)

INCOME TAX (Details) - USD ($)	10 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
INCOME TAX [Abstract]
Deferred tax assets, net	$ 0	$ 0	$ 0
Deferred tax liabilities, net	0	0	0
Federal [Abstract]
Federal, Current	373,079	2,645
Federal, Deferred	0	0
State and Local [Abstract]
State and local, Current	0	0
State and local, Deferred	0	0
Change in valuation allowance	0	0
Income tax provision	373,079	2,645
Federal and State net operating loss carryovers	$ 0	$ 0	$ 0
Reconciliation of Federal Income Tax Rate [Abstract]
Statutory federal income tax rate		21.00%	21.00%
State taxes, net of federal tax benefit		0.00%	0.00%
Business Combinations		(21.10%)	0.00%
Valuation allowance		0.00%	0.00%
Income tax provision		(0.10%)	21.00%

FAIR VALUE MEASUREMENTS (Detail

FAIR VALUE MEASUREMENTS (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Recurring [Member] | Level 1 [Member]
Assets [Abstract]
Marketable securities held in Trust Account	$ 252,292,955	$ 251,865,941