$ALRM
Alarm.com Holdings, Inc. Stock $alrm

$alrm Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000145920021000012 Filed on February 25, 2021

Income Statement

Concept	2020 Q4	2019 Q4	2019 Q3
Revenue	$165.6M	$140.5M	$127.9M
YoY Change	17.86%	26.11%	14.33%
Cost Of Revenue	$59.26M	$52.57M	$47.52M
YoY Change	12.73%	35.29%	13.17%
Gross Profit	$106.3M	$87.92M	$80.36M
YoY Change	20.93%	21.19%	15.03%
Gross Profit Margin	64.21%	62.58%	62.84%
Selling, General & Admin	$46.60M	$36.60M	$33.23M
YoY Change	27.32%	7.33%	-42.49%
% of Gross Profit	43.83%	41.63%	41.36%
Research & Development	$38.90M	$30.10M	$29.46M
YoY Change	29.24%	23.36%	28.83%
% of Gross Profit	36.59%	34.24%	36.66%
Depreciation & Amortization	$7.800M	$6.500M	$5.600M
YoY Change	20.0%	14.04%	-8.2%
% of Gross Profit	7.34%	7.39%	6.97%
Operating Expenses	$92.90M	$72.90M	$68.16M
YoY Change	27.43%	13.73%	-21.25%
Operating Profit	$13.42M	$15.02M	$12.20M
YoY Change	-10.67%	77.85%	-173.05%
Interest Expense	-$400.0K	$0.00	$2.000M
YoY Change		-100.0%	-385.71%
% of Operating Profit	-2.98%	0.0%	16.4%
Other Income/Expense, Net	$700.0K	$100.0K	$6.380M
YoY Change	600.0%	-88.89%	11292.86%
Pretax Income	$13.70M	$15.00M	$20.56M
YoY Change	-8.67%	76.47%	-223.04%
Income Tax	-$2.000M	$2.100M	$2.900M
% Of Pretax Income	-14.6%	14.0%	14.1%
Net Earnings	$15.97M	$13.04M	$17.69M
YoY Change	22.49%	64.42%	-331.18%
Net Earnings / Revenue	9.64%	9.28%	13.83%
Basic Earnings Per Share	$0.32	$0.27	$0.36
Diluted Earnings Per Share	$0.31	$0.26	$0.35
COMMON SHARES
Basic Shares Outstanding	49.11M shares	48.57M shares	48.52M shares
Diluted Shares Outstanding			50.15M shares

Balance Sheet

Concept	2020 Q4	2019 Q4	2019 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$253.5M	$119.6M	$164.3M
YoY Change	111.96%	-18.14%	32.29%
Cash & Equivalents	$253.5M	$119.6M	$164.3M
Short-Term Investments
Other Short-Term Assets	$16.35M	$13.50M	$13.50M
YoY Change	21.06%	42.12%	-19.98%
Inventory	$44.28M	$34.17M	$20.98M
Prepaid Expenses
Receivables	$83.33M	$76.37M	$64.90M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$397.4M	$243.7M	$263.7M
YoY Change	63.09%	6.85%	23.52%
LONG-TERM ASSETS
Property, Plant & Equipment	$44.80M	$38.55M	$32.33M
YoY Change	16.21%	38.88%	14.05%
Goodwill	$112.8M	$105.0M	$63.59M
YoY Change	7.5%	65.06%	0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$18.23M	$17.52M	$17.62M
YoY Change	4.09%	29.22%	41.15%
Total Long-Term Assets	$334.3M	$314.1M	$237.3M
YoY Change	6.41%	47.53%	10.95%
TOTAL ASSETS
Total Short-Term Assets	$397.4M	$243.7M	$263.7M
Total Long-Term Assets	$334.3M	$314.1M	$237.3M
Total Assets	$731.7M	$557.8M	$501.0M
YoY Change	31.17%	26.49%	17.23%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$38.16M	$32.88M	$20.69M
YoY Change	16.07%	62.65%	5.33%
Accrued Expenses	$11.45M	$10.09M	$9.234M
YoY Change	13.45%	-70.8%	-73.62%
Deferred Revenue	$4.037M	$3.043M	$3.063M
YoY Change	32.67%	-9.33%	-13.45%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$90.24M	$75.80M	$56.71M
YoY Change	19.06%	0.7%	-22.33%
LONG-TERM LIABILITIES
Long-Term Debt	$110.0M	$63.00M	$64.00M
YoY Change	74.6%	-5.97%	-5.88%
Other Long-Term Liabilities	$6.811M	$7.489M	$1.884M
YoY Change	-9.05%	-43.72%	-85.81%
Total Long-Term Liabilities	$116.8M	$70.49M	$65.88M
YoY Change	65.72%	-12.22%	-18.94%
TOTAL LIABILITIES
Total Short-Term Liabilities	$90.24M	$75.80M	$56.71M
Total Long-Term Liabilities	$116.8M	$70.49M	$65.88M
Total Liabilities	$253.2M	$190.9M	$164.8M
YoY Change	32.63%	16.86%	1.37%
SHAREHOLDERS EQUITY
Retained Earnings	$66.57M	-$10.46M	-$23.50M
YoY Change	-736.28%	-83.66%	-67.35%
Common Stock	$496.0K	$487.0K	$486.0K
YoY Change	1.85%	1.25%	1.25%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$5.149M	$0.00
YoY Change
Treasury Stock Shares	147.2K shares	0.000 shares
Shareholders Equity	$467.8M	$355.7M	$336.2M
YoY Change
Total Liabilities & Shareholders Equity	$731.7M	$557.8M	$501.0M
YoY Change	31.17%	26.49%	17.23%

Cashflow Statement

Concept	2020 Q4	2019 Q4	2019 Q3
OPERATING ACTIVITIES
Net Income	$15.97M	$13.04M	$17.69M
YoY Change	22.49%	64.42%	-331.18%
Depreciation, Depletion And Amortization	$7.800M	$6.500M	$5.600M
YoY Change	20.0%	14.04%	-8.2%
Cash From Operating Activities	$35.40M	$23.30M	$900.0K
YoY Change	51.93%	-9.34%	-95.45%
INVESTING ACTIVITIES
Capital Expenditures	-$5.600M	-$8.700M	-$5.800M
YoY Change	-35.63%	210.71%	81.25%
Acquisitions
YoY Change
Other Investing Activities	-$26.90M	-$58.80M	$18.30M
YoY Change	-54.25%	4423.08%
Cash From Investing Activities	-$32.50M	-$67.50M	$12.50M
YoY Change	-51.85%	1546.34%	-490.62%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	3.400M	-400.0K	0.000
YoY Change	-950.0%	-500.0%	-100.0%
NET CHANGE
Cash From Operating Activities	35.40M	23.30M	900.0K
Cash From Investing Activities	-32.50M	-67.50M	12.50M
Cash From Financing Activities	3.400M	-400.0K	0.000
Net Change In Cash	6.300M	-44.60M	13.40M
YoY Change	-114.13%	-305.53%	-26.78%
FREE CASH FLOW
Cash From Operating Activities	$35.40M	$23.30M	$900.0K
Capital Expenditures	-$5.600M	-$8.700M	-$5.800M
Free Cash Flow	$41.00M	$32.00M	$6.700M
YoY Change	28.12%	12.28%	-70.87%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0001459200
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2017	us-gaap	Accounting Standards Update Extensible List AccountingStandardsUpdateExtensibleList	us-gaap:AccountingStandardsUpdate201409Member
CY2018	us-gaap	Accounting Standards Update Extensible List AccountingStandardsUpdateExtensibleList	us-gaap:AccountingStandardsUpdate201602Member
CY2019	us-gaap	Accounting Standards Update Extensible List AccountingStandardsUpdateExtensibleList	us-gaap:AccountingStandardsUpdate201613Member
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-37461
CY2020	dei	Entity Registrant Name EntityRegistrantName	ALARM.COM HOLDINGS, INC.
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	26-4247032
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	8281 Greensboro Drive
CY2020	dei	Entity Address Address Line2 EntityAddressAddressLine2	Suite 100
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Tysons
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	VA
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	22102
CY2020	dei	City Area Code CityAreaCode	877
CY2020	dei	Local Phone Number LocalPhoneNumber	389-4033
CY2020	dei	Security12b Title Security12bTitle	Common Stock, $0.01 par value per share
CY2020	dei	Trading Symbol TradingSymbol	ALRM
CY2020	dei	Security Exchange Name SecurityExchangeName	NASDAQ
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2020	dei	Entity Small Business EntitySmallBusiness	false
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2020	dei	Entity Shell Company EntityShellCompany	false
CY2020Q2	dei	Entity Public Float EntityPublicFloat	2300000000	USD
CY2021Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	49586789	shares
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	618003000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	502363000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	420494000	USD
CY2020	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	227428000	USD
CY2019	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	183599000	USD
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CY2020	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	78643000	USD
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CY2018	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	95750000	USD
CY2020	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	152147000	USD
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CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	27520000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	22134000	USD
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CY2019	us-gaap	Operating Expenses OperatingExpenses	268351000	USD
CY2018	us-gaap	Operating Expenses OperatingExpenses	262577000	USD
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	56298000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	50413000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	12202000	USD
CY2020	us-gaap	Interest Expense Long Term Debt InterestExpenseLongTermDebt	2596000	USD
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CY2018	us-gaap	Interest Expense Long Term Debt InterestExpenseLongTermDebt	2918000	USD
CY2020	us-gaap	Interest Income Other InterestIncomeOther	870000	USD
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CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	25588000	USD
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CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3500000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	5566000	USD
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CY2020	us-gaap	Profit Loss ProfitLoss	76660000	USD
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CY2019Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	0	shares
CY2020Q4	us-gaap	Treasury Stock Value TreasuryStockValue	5149000	USD
CY2019Q4	us-gaap	Treasury Stock Value TreasuryStockValue	0	USD
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	66574000	USD
CY2019Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-10463000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	467752000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	355651000	USD
CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	731687000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	557799000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	76660000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	53330000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	21524000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	2162000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1170000	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	149000	USD
CY2020	alrm	Contract With Customer Provision For Product Returns ContractWithCustomerProvisionForProductReturns	1795000	USD
CY2019	alrm	Contract With Customer Provision For Product Returns ContractWithCustomerProvisionForProductReturns	-123000	USD
CY2018	alrm	Contract With Customer Provision For Product Returns ContractWithCustomerProvisionForProductReturns	273000	USD
CY2020	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-359000	USD
CY2019	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-3272000	USD
CY2018	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	3319000	USD
CY2020	us-gaap	Inventory Write Down InventoryWriteDown	1451000	USD
CY2019	us-gaap	Inventory Write Down InventoryWriteDown	485000	USD
CY2018	us-gaap	Inventory Write Down InventoryWriteDown	0	USD
CY2020	us-gaap	Cost Of Goods And Services Sold Amortization CostOfGoodsAndServicesSoldAmortization	882000	USD
CY2019	us-gaap	Cost Of Goods And Services Sold Amortization CostOfGoodsAndServicesSoldAmortization	700000	USD
CY2018	us-gaap	Cost Of Goods And Services Sold Amortization CostOfGoodsAndServicesSoldAmortization	900000	USD
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	27520000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	22134000	USD
CY2018	us-gaap	Depreciation And Amortization DepreciationAndAmortization	21721000	USD
CY2020	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	108000	USD
CY2019	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	108000	USD
CY2018	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	108000	USD
CY2020	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	8888000	USD
CY2019	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	7600000	USD
CY2018	us-gaap	Operating Lease Right Of Use Asset Amortization Expense OperatingLeaseRightOfUseAssetAmortizationExpense	0	USD
CY2020	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-3256000	USD
CY2019	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	2599000	USD
CY2018	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	-11482000	USD
CY2020	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	-2595000	USD
CY2019	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	-198000	USD
CY2018	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	0	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	29176000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	20603000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	13429000	USD
CY2020	alrm	Gain Losson Notes Receivable GainLossonNotesReceivable	0	USD
CY2019	alrm	Gain Losson Notes Receivable GainLossonNotesReceivable	-6931000	USD
CY2018	alrm	Gain Losson Notes Receivable GainLossonNotesReceivable	0	USD
CY2020	us-gaap	Research And Development In Process ResearchAndDevelopmentInProcess	3297000	USD
CY2019	us-gaap	Research And Development In Process ResearchAndDevelopmentInProcess	850000	USD
CY2018	us-gaap	Research And Development In Process ResearchAndDevelopmentInProcess	0	USD
CY2020	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	24737000	USD
CY2019	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	0	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	16141000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	19324000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	11015000	USD
CY2020	alrm	Paymentsfor Asset Acquisitions PaymentsforAssetAcquisitions	3297000	USD
CY2019	alrm	Paymentsfor Asset Acquisitions PaymentsforAssetAcquisitions	850000	USD
CY2018	alrm	Paymentsfor Asset Acquisitions PaymentsforAssetAcquisitions	0	USD
CY2020	us-gaap	Payments To Acquire Notes Receivable PaymentsToAcquireNotesReceivable	1200000	USD
CY2018	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	0	USD
CY2020	us-gaap	Asset Impairment Charges AssetImpairmentCharges	-676000	USD
CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	605000	USD
CY2018	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	USD
CY2020	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	0	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	0	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-1410000	USD
CY2020	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	10098000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	22273000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	9298000	USD
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	10647000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	6976000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	8813000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2683000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	2887000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-115000	USD
CY2020	alrm	Increase Decreasein Accounts Payable Accrued Liabilitiesand Other Current Liabilities IncreaseDecreaseinAccountsPayableAccruedLiabilitiesandOtherCurrentLiabilities	13781000	USD
CY2019	us-gaap	Payments To Acquire Notes Receivable PaymentsToAcquireNotesReceivable	26103000	USD
CY2018	us-gaap	Payments To Acquire Notes Receivable PaymentsToAcquireNotesReceivable	1287000	USD
CY2019	alrm	Increase Decreasein Accounts Payable Accrued Liabilitiesand Other Current Liabilities IncreaseDecreaseinAccountsPayableAccruedLiabilitiesandOtherCurrentLiabilities	-10980000	USD
CY2018	alrm	Increase Decreasein Accounts Payable Accrued Liabilitiesand Other Current Liabilities IncreaseDecreaseinAccountsPayableAccruedLiabilitiesandOtherCurrentLiabilities	30615000	USD
CY2020	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	2031000	USD
CY2019	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	-1567000	USD
CY2018	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	-1502000	USD
CY2020	alrm	Increase Decrease In Operating Lease Liabilities IncreaseDecreaseInOperatingLeaseLiabilities	-10177000	USD
CY2019	alrm	Increase Decrease In Operating Lease Liabilities IncreaseDecreaseInOperatingLeaseLiabilities	-8268000	USD
CY2018	alrm	Increase Decrease In Operating Lease Liabilities IncreaseDecreaseInOperatingLeaseLiabilities	0	USD
CY2020	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-443000	USD
CY2019	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	403000	USD
CY2018	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-1758000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	102080000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	47112000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	60710000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	26299000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	58833000	USD
CY2020	alrm	Proceeds From Notes Receivable Repayments ProceedsFromNotesReceivableRepayments	2026000	USD
CY2019	alrm	Proceeds From Notes Receivable Repayments ProceedsFromNotesReceivableRepayments	31696000	USD
CY2018	alrm	Proceeds From Notes Receivable Repayments ProceedsFromNotesReceivableRepayments	0	USD
CY2020	us-gaap	Proceeds From Sale Of Investment Projects ProceedsFromSaleOfInvestmentProjects	25687000	USD
CY2019	us-gaap	Proceeds From Sale Of Investment Projects ProceedsFromSaleOfInvestmentProjects	0	USD
CY2018	us-gaap	Proceeds From Sale Of Investment Projects ProceedsFromSaleOfInvestmentProjects	0	USD
CY2020	us-gaap	Payments To Acquire Intangible Assets PaymentsToAcquireIntangibleAssets	1050000	USD
CY2019	us-gaap	Payments To Acquire Intangible Assets PaymentsToAcquireIntangibleAssets	0	USD
CY2018	us-gaap	Payments To Acquire Intangible Assets PaymentsToAcquireIntangibleAssets	1075000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-20274000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-73414000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-13377000	USD
CY2020	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	50000000	USD
CY2019	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	0	USD
CY2018	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	0	USD
CY2020	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	3000000	USD
CY2019	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	4000000	USD
CY2018	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	4000000	USD
CY2020	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	1538000	USD
CY2019	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	0	USD
CY2018	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	0	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	5149000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1000	USD
CY2020	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	11711000	USD
CY2019	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	3870000	USD
CY2018	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	6400000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	52024000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-130000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	2399000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	133830000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-26432000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	49732000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	119629000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	146061000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	96329000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	253459000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	119629000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	146061000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	2427000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	2730000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	2695000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	7369000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	2254000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-2052000	USD
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	2020000	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	837000	USD
CY2018	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	1857000	USD
CY2020	alrm	Business Combination Consideration Transferred Incurredbut Notyet Paid BusinessCombinationConsiderationTransferredIncurredbutNotyetPaid	1017000	USD
CY2019	alrm	Business Combination Consideration Transferred Incurredbut Notyet Paid BusinessCombinationConsiderationTransferredIncurredbutNotyetPaid	2970000	USD
CY2018	alrm	Business Combination Consideration Transferred Incurredbut Notyet Paid BusinessCombinationConsiderationTransferredIncurredbutNotyetPaid	0	USD
CY2020	alrm	Business Combination Consideration Transferred Contingent Liability BusinessCombinationConsiderationTransferredContingentLiability	0	USD
CY2019	alrm	Business Combination Consideration Transferred Contingent Liability BusinessCombinationConsiderationTransferredContingentLiability	2595000	USD
CY2018	alrm	Business Combination Consideration Transferred Contingent Liability BusinessCombinationConsiderationTransferredContingentLiability	0	USD
CY2017Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	0	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	232827000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	6400000	USD
CY2018	alrm	Stock Issued During Period Value Vestingof Common Stock Subjectto Repurchase StockIssuedDuringPeriodValueVestingofCommonStockSubjecttoRepurchase	55000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	13661000	USD
CY2018	us-gaap	Net Income Loss Including Portion Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest	21524000	USD
CY2018Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	0	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	277589000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	3870000	USD
CY2019	alrm	Stock Issued During Period Value Vestingof Common Stock Subjectto Repurchase StockIssuedDuringPeriodValueVestingofCommonStockSubjecttoRepurchase	8000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	20616000	USD
CY2019	alrm	Temporary Equity Noncontrolling Interest Assumed Through Acquisition TemporaryEquityNoncontrollingInterestAssumedThroughAcquisition	11411000	USD
CY2019	us-gaap	Temporary Equity Net Income TemporaryEquityNetIncome	-201000	USD
CY2019	us-gaap	Net Income Loss Including Portion Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest	53531000	USD
CY2019Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	11210000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	355651000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	11711000	USD
CY2020	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	5149000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	29176000	USD
CY2020	us-gaap	Temporary Equity Accretion To Redemption Value Adjustment TemporaryEquityAccretionToRedemptionValueAdjustment	-674000	USD
CY2020	alrm	Adjustments To Additional Paid In Capital Accretion Adjustments Of Redeemable Noncontrolling Interest To Redemption Value AdjustmentsToAdditionalPaidInCapitalAccretionAdjustmentsOfRedeemableNoncontrollingInterestToRedemptionValue	674000	USD
CY2020	us-gaap	Temporary Equity Net Income TemporaryEquityNetIncome	-1193000	USD
CY2020	us-gaap	Net Income Loss Including Portion Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest	77853000	USD
CY2020Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	10691000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	467752000	USD
CY2020	us-gaap	Nature Of Operations NatureOfOperations	OrganizationAlarm.com Holdings, Inc. (referred to herein as Alarm.com, the Company, or we) is the leading platform for the intelligently connected property. We offer a comprehensive suite of cloud-based solutions for the smart residential and commercial property, including interactive security, video monitoring, intelligent automation and energy management. Millions of property owners depend on our technology to intelligently secure, automate and manage their residential and commercial properties. Our solutions are delivered through an established network of over 10,000 trusted service provider partners, who are experts at selling, installing and supporting our solutions. We derive revenue from the sale of our cloud-based Software-as-a-Service, or SaaS, services, license fees, software, hardware, activation fees and other revenue. Our fiscal year ends on December 31.
CY2020Q4	alrm	Trusted Service Providers TrustedServiceProviders	10000	service_provider
CY2019	alrm	Accounts And Notes Receivable Credit Loss Expense Reversal AccountsAndNotesReceivableCreditLossExpenseReversal	-2100000	USD
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates</span></div><div><span><br/></span></div><div style="text-indent:18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America, or GAAP, requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. As of the date of issuance of these financial statements, we are not aware of any specific event or circumstance that would require us to update our estimates, assumptions and judgments or revise the carrying value of our assets or liabilities. However, our estimates, judgments and assumptions are continually evaluated based on available information and experience and may change as new events occur and additional information is obtained. Because of the use of estimates inherent in the financial reporting process and in light of the continuing uncertainty arising from the COVID-19 pandemic, actual results could differ from those estimates and any such differences may be material. Estimates are used when accounting for revenue recognition, allowances for credit losses, allowance for hardware returns, estimates of obsolete inventory, long-term incentive compensation, the lease term and incremental borrowing rate for leases, stock-based compensation, income taxes, legal reserves, contingent consideration and goodwill and intangible assets.</span></div>
CY2020	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-style:italic;font-weight:700;line-height:120%">Reclassifications</span></div><div><span><br/></span></div><div style="text-indent:18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">Certain previously reported amounts in the consolidated statements of cash flows for the years ended December 31, 2019 have been reclassified to conform to our current presentation, including the addition of a provision for excess and obsolete inventory separate line item, which was previously included in inventory.</span></div>
CY2020	alrm	Accounts And Notes Receivable Credit Loss Expense Reversal AccountsAndNotesReceivableCreditLossExpenseReversal	1700000	USD
CY2018	alrm	Accounts And Notes Receivable Credit Loss Expense Reversal AccountsAndNotesReceivableCreditLossExpenseReversal	3500000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	0	USD
CY2019Q4	alrm	Sublease Liability SubleaseLiability	0	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	0	USD
CY2020Q4	alrm	Sublease Liability SubleaseLiability	0	USD
CY2020Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	10700000	USD
CY2019Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	11200000	USD
CY2020	alrm	Revenue Recognition Number Of Primary Revenue Sources RevenueRecognitionNumberOfPrimaryRevenueSources	3	source
CY2020	alrm	Revenue Recognition Service Provider Contract Term RevenueRecognitionServiceProviderContractTerm	P1Y
CY2020	alrm	Revenue Recognition Service Provider Contract Renewal Term RevenueRecognitionServiceProviderContractRenewalTerm	P1Y
CY2020	alrm	Revenue Recognition Sales Returns Reservefor Sales Returns Percentage RevenueRecognitionSalesReturnsReserveforSalesReturnsPercentage	0.01
CY2019	alrm	Revenue Recognition Sales Returns Reservefor Sales Returns Percentage RevenueRecognitionSalesReturnsReserveforSalesReturnsPercentage	0.01
CY2018	alrm	Revenue Recognition Sales Returns Reservefor Sales Returns Percentage RevenueRecognitionSalesReturnsReserveforSalesReturnsPercentage	0.02
CY2020	alrm	Revenue Recognition Sales Returns Period RevenueRecognitionSalesReturnsPeriod	P1Y
CY2020Q4	us-gaap	Capitalized Contract Cost Amortization Period CapitalizedContractCostAmortizationPeriod	P3Y
CY2020Q4	us-gaap	Capitalized Contract Cost Amortization Period CapitalizedContractCostAmortizationPeriod	P3Y
CY2020	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-style:italic;font-weight:700;line-height:120%">Concentration of Credit Risk</span></div><div><span><br/></span></div><div style="text-indent:18pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">The financial instruments that potentially subject us to concentrations of credit risk consists principally of cash and cash equivalents and accounts receivables. All of our cash and cash equivalents are held at financial institutions that management believes to be of high credit quality. Our cash and cash equivalent accounts may exceed federally insured limits at times. We have not experienced any losses on cash and cash equivalents to date. To manage accounts receivable risk, we evaluate the credit worthiness of our service provider partners and maintain an allowance for doubtful accounts. The majority of our accounts receivable balance is due from our service provider partners in North America. We assess the concentrations of credit risk with respect to accounts receivables based on one industry and one geographic region and believe that our reserve for uncollectable accounts is appropriate based on our history and this concentration.</span></div>
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	P5Y
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	29200000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	20600000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	13400000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	8200000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	5200000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	7600000	USD
CY2020Q4	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	USD
CY2019	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	USD
CY2020	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	USD
CY2020	us-gaap	Advertising Expense AdvertisingExpense	11900000	USD
CY2019	us-gaap	Advertising Expense AdvertisingExpense	7500000	USD
CY2018	us-gaap	Advertising Expense AdvertisingExpense	11400000	USD
CY2019	us-gaap	Capitalized Contract Cost Impairment Loss CapitalizedContractCostImpairmentLoss	0	USD
CY2020	us-gaap	Capitalized Contract Cost Impairment Loss CapitalizedContractCostImpairmentLoss	0	USD
CY2018	us-gaap	Capitalized Contract Cost Impairment Loss CapitalizedContractCostImpairmentLoss	0	USD
CY2019Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	4578000	USD
CY2018Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	2881000	USD
CY2017Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	0	USD
CY2020	alrm	Contract With Customer Asset Commission Costsand Upfront Payments To A Customer Capitalized During Period ContractWithCustomerAssetCommissionCostsandUpfrontPaymentsToACustomerCapitalizedDuringPeriod	3262000	USD
CY2019	alrm	Contract With Customer Asset Commission Costsand Upfront Payments To A Customer Capitalized During Period ContractWithCustomerAssetCommissionCostsandUpfrontPaymentsToACustomerCapitalizedDuringPeriod	4141000	USD
CY2018	alrm	Contract With Customer Asset Commission Costsand Upfront Payments To A Customer Capitalized During Period ContractWithCustomerAssetCommissionCostsandUpfrontPaymentsToACustomerCapitalizedDuringPeriod	4864000	USD
CY2020	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	3534000	USD
CY2019	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	2444000	USD
CY2018	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	1983000	USD
CY2020Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	4306000	USD
CY2019Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	4578000	USD
CY2018Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	2881000	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	10498000	USD
CY2018Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	11176000	USD
CY2017Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	12678000	USD
CY2020	alrm	Contract With Customer Liability Revenue Deferred During Period ContractWithCustomerLiabilityRevenueDeferredDuringPeriod	12247000	USD
CY2019	alrm	Contract With Customer Liability Revenue Deferred During Period ContractWithCustomerLiabilityRevenueDeferredDuringPeriod	6127000	USD
CY2018	alrm	Contract With Customer Liability Revenue Deferred During Period ContractWithCustomerLiabilityRevenueDeferredDuringPeriod	3954000	USD
CY2020	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	10216000	USD
CY2019	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	6805000	USD
CY2018	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	5456000	USD
CY2020Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	12529000	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	10498000	USD
CY2018Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	11176000	USD
CY2020Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	89502000	USD
CY2019Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	80032000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	4696000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	2584000	USD
CY2020Q4	alrm	Allowancefor Product Returns Current AllowanceforProductReturnsCurrent	1480000	USD
CY2019Q4	alrm	Allowancefor Product Returns Current AllowanceforProductReturnsCurrent	1075000	USD
CY2020Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	83326000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	76373000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	2200000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1200000	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	100000	USD
CY2020Q4	us-gaap	Inventory Raw Materials Net Of Reserves InventoryRawMaterialsNetOfReserves	9475000	USD
CY2019Q4	us-gaap	Inventory Raw Materials Net Of Reserves InventoryRawMaterialsNetOfReserves	8921000	USD
CY2020Q4	us-gaap	Inventory Finished Goods Net Of Reserves InventoryFinishedGoodsNetOfReserves	34806000	USD
CY2019Q4	us-gaap	Inventory Finished Goods Net Of Reserves InventoryFinishedGoodsNetOfReserves	25247000	USD
CY2020Q4	us-gaap	Inventory Net InventoryNet	44281000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	34168000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	80203000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	66090000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	35407000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	27542000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	44796000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	38548000	USD
CY2020	us-gaap	Depreciation Depreciation	8300000	USD
CY2019	us-gaap	Depreciation Depreciation	5900000	USD
CY2018	us-gaap	Depreciation Depreciation	5700000	USD
CY2020	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	2400000	USD
CY2019	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	1900000	USD
CY2018	us-gaap	Capitalized Computer Software Amortization1 CapitalizedComputerSoftwareAmortization1	800000	USD
CY2020	us-gaap	Property Plant And Equipment Disposals PropertyPlantAndEquipmentDisposals	0	USD
CY2019	us-gaap	Property Plant And Equipment Disposals PropertyPlantAndEquipmentDisposals	0	USD
CY2018	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018	us-gaap	Property Plant And Equipment Disposals PropertyPlantAndEquipmentDisposals	1400000	USD
CY2019Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	11400000	USD
CY2020Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	10700000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	63591000	USD
CY2019	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	41372000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	104963000	USD
CY2020	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	7176000	USD
CY2020	us-gaap	Goodwill Purchase Accounting Adjustments GoodwillPurchaseAccountingAdjustments	699000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	112838000	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	79067000	USD
CY2019	us-gaap	Finitelived Intangible Assets Acquired1 FinitelivedIntangibleAssetsAcquired1	38607000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	14236000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	103438000	USD
CY2020	us-gaap	Finitelived Intangible Assets Acquired1 FinitelivedIntangibleAssetsAcquired1	16396000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	16575000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	103259000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	16600000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	14200000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	15200000	USD
CY2018	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	USD
CY2019	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	USD
CY2020	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	174206000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	70947000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	103259000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	157811000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	54373000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	103438000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	17044000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	17534000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	16193000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	14257000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	12071000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	26160000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	103259000	USD
CY2020Q4	alrm	Financing Receivable Amortized Cost Nonaccrual FinancingReceivableAmortizedCostNonaccrual	9000	USD
CY2019Q4	alrm	Financing Receivable Amortized Cost Nonaccrual FinancingReceivableAmortizedCostNonaccrual	16000	USD
CY2020	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0	USD
CY2018	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0	USD
CY2019	us-gaap	Financing Receivable Nonaccrual Interest Income FinancingReceivableNonaccrualInterestIncome	0	USD
CY2020Q4	us-gaap	Prepaid Expense Current And Noncurrent PrepaidExpenseCurrentAndNoncurrent	8400000	USD
CY2019Q4	us-gaap	Prepaid Expense Current And Noncurrent PrepaidExpenseCurrentAndNoncurrent	6100000	USD
CY2018	us-gaap	Impairment Of Investments ImpairmentOfInvestments	0	USD
CY2020	us-gaap	Impairment Of Investments ImpairmentOfInvestments	0	USD
CY2019	us-gaap	Impairment Of Investments ImpairmentOfInvestments	0	USD
CY2020Q4	alrm	Operating Lease Available Leasehold Improvement Allowance OperatingLeaseAvailableLeaseholdImprovementAllowance	11800000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	8888000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	7600000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	10177000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	8268000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	10073000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	7886000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P4Y10M24D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P5Y8M12D
CY2020Q4	us-gaap	Lessee Operating Lease Discount Rate LesseeOperatingLeaseDiscountRate	0.036
CY2019Q4	us-gaap	Lessee Operating Lease Discount Rate LesseeOperatingLeaseDiscountRate	0.040
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	11485000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	10460000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	9648000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	8494000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	7539000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	4443000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	52069000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	4399000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	47670000	USD
CY2020Q4	alrm	Lessee Operating Lease Lease Not Yet Commenced Minimum Lease Payments LesseeOperatingLeaseLeaseNotYetCommencedMinimumLeasePayments	100000	USD
CY2020Q4	alrm	Lessee Operating Lease Option To Extend Amount LesseeOperatingLeaseOptionToExtendAmount	1000000.0	USD
CY2018	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	6300000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	7044000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	7168000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	6974000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	6719000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	6348000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	14838000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	49091000	USD
CY2020Q4	alrm	Common Stock Voting Rights Votes Per Share CommonStockVotingRightsVotesPerShare	1
CY2018Q4	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	75000000.0	USD
CY2018Q4	us-gaap	Stock Repurchase Program Period In Force1 StockRepurchaseProgramPeriodInForce1	P2Y
CY2019Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	3244000	USD
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	6811000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	7489000	USD
CY2020Q4	alrm	Numberof Stock Classes NumberofStockClasses	2	class_of_stock
CY2015Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	300000000	shares
CY2015Q3	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	10000000	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	49630773	shares
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	48700963	shares
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	49483620	shares
CY2019Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	48700713	shares
CY2020Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2020Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2019Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2019Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2020Q4	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	100000000.0	USD
CY2020Q4	us-gaap	Stock Repurchase Program Period In Force1 StockRepurchaseProgramPeriodInForce1	P3Y
CY2020	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	147153	shares
CY2019	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	0	shares
CY2018	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	0	shares
CY2020Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	38163000	USD
CY2019Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	32878000	USD
CY2020Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	11449000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	10092000	USD
CY2020Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	4315000	USD
CY2019Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	5757000	USD
CY2020Q4	alrm	Accounts Payable Accrued Liabilitiesand Other Current Liabilities Current AccountsPayableAccruedLiabilitiesandOtherCurrentLiabilitiesCurrent	53927000	USD
CY2019Q4	alrm	Accounts Payable Accrued Liabilitiesand Other Current Liabilities Current AccountsPayableAccruedLiabilitiesandOtherCurrentLiabilitiesCurrent	48727000	USD
CY2020Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	0	USD
CY2019Q4	us-gaap	Business Combination Contingent Consideration Liability BusinessCombinationContingentConsiderationLiability	2595000	USD
CY2020Q4	alrm	Business Combination Consideration Transferred Holdback Amount BusinessCombinationConsiderationTransferredHoldbackAmount	1500000	USD
CY2019Q4	alrm	Business Combination Consideration Transferred Holdback Amount BusinessCombinationConsiderationTransferredHoldbackAmount	1650000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	5311000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	29176000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	20603000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	13429000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	29176000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	20603000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	13429000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	8202000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	5154000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	7581000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	143650	shares
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	186500	shares
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	219450	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	1905751	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	20.60
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P6Y
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	45344000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	143650	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	40.89
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	696154	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	14.70
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	33423000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	8403	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	34.55
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod	1365	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice	6.65
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	1343479	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	25.75
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P5Y8M12D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	104388000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber	1343479	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice	25.75
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested And Expected To Vest Outstanding Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1	P5Y8M12D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Aggregate Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue	104388000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber	878901	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice	16.54
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested And Expected To Vest Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1	P4Y7M6D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Exercisable Aggregate Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue	76382000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	16.79
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	25.01
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	19.43
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	3600000	USD
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	3400000	USD
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	3500000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	33400000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	15100000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	32700000	USD
CY2020Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Stock Options EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions	4100000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	10200000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	2500000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	5200000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	76660000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	53330000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	21524000	USD
CY2020	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	-1193000	USD
CY2019	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	-201000	USD
CY2018	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	0	USD
CY2020	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	0	USD
CY2019	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	0	USD
CY2018	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Basic UndistributedEarningsLossAllocatedToParticipatingSecuritiesBasic	3000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	77853000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	53531000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	21521000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	48950328	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	48427446	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	47633739	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	2012862	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1846443	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	2058445	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50963190	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50273889	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49692184	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.59
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.11
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.45
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.53
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.06
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.43
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	3583000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	1615000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	741000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	2735000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	900000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	653000	USD
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	438000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	452000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	263000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	6756000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	2967000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	1657000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-3628000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	2622000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-8821000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	372000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-23000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-2643000	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	0	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	0	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-18000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-3256000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	2599000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-11482000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3500000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	5566000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-9825000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.014
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.006
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	-0.034
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Meals And Entertainment EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMealsAndEntertainment	0.001
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Meals And Entertainment EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMealsAndEntertainment	0.008
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Meals And Entertainment EffectiveIncomeTaxRateReconciliationNondeductibleExpenseMealsAndEntertainment	0.021
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense EffectiveIncomeTaxRateReconciliationNondeductibleExpense	0
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense EffectiveIncomeTaxRateReconciliationNondeductibleExpense	0
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense EffectiveIncomeTaxRateReconciliationNondeductibleExpense	0.013
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Deductions Extraterritorial Income Exclusion EffectiveIncomeTaxRateReconciliationDeductionsExtraterritorialIncomeExclusion	0.014
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Deductions Extraterritorial Income Exclusion EffectiveIncomeTaxRateReconciliationDeductionsExtraterritorialIncomeExclusion	0.007
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Deductions Extraterritorial Income Exclusion EffectiveIncomeTaxRateReconciliationDeductionsExtraterritorialIncomeExclusion	0
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0.013
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.094
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.071
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Research EffectiveIncomeTaxRateReconciliationTaxCreditsResearch	0.487
CY2020	alrm	Effective Income Tax Rate Reconciliation Tax Windfall Benefits EffectiveIncomeTaxRateReconciliationTaxWindfallBenefits	0.088
CY2019	alrm	Effective Income Tax Rate Reconciliation Tax Windfall Benefits EffectiveIncomeTaxRateReconciliationTaxWindfallBenefits	0.075
CY2018	alrm	Effective Income Tax Rate Reconciliation Tax Windfall Benefits EffectiveIncomeTaxRateReconciliationTaxWindfallBenefits	0.557
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	-0.002
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0.004
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	-0.014
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Reconciling Items Percent EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent	0.004
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Reconciling Items Percent EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent	0.020
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Reconciling Items Percent EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent	0.008
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.044
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.095
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.840
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	1524000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Allowance For Doubtful Accounts DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts	606000	USD
CY2020Q4	alrm	Deferred Tax Assets Depreciation DeferredTaxAssetsDepreciation	261000	USD
CY2019Q4	alrm	Deferred Tax Assets Depreciation DeferredTaxAssetsDepreciation	267000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	4633000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	3114000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	1725000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	2060000	USD
CY2020Q4	alrm	Deferred Tax Assets Operating Lease Liabilities DeferredTaxAssetsOperatingLeaseLiabilities	11511000	USD
CY2019Q4	alrm	Deferred Tax Assets Operating Lease Liabilities DeferredTaxAssetsOperatingLeaseLiabilities	10929000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	12768000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	8840000	USD
CY2020Q4	alrm	Deferred Tax Assets Tax Deferred Expense Business Combination Costs DeferredTaxAssetsTaxDeferredExpenseBusinessCombinationCosts	2773000	USD
CY2019Q4	alrm	Deferred Tax Assets Tax Deferred Expense Business Combination Costs DeferredTaxAssetsTaxDeferredExpenseBusinessCombinationCosts	2811000	USD
CY2020Q4	alrm	Deferred Tax Assets Tax Deferred Expense Subsidiary Unit Compensation DeferredTaxAssetsTaxDeferredExpenseSubsidiaryUnitCompensation	249000	USD
CY2019Q4	alrm	Deferred Tax Assets Tax Deferred Expense Subsidiary Unit Compensation DeferredTaxAssetsTaxDeferredExpenseSubsidiaryUnitCompensation	185000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Equity Method Investments DeferredTaxAssetsEquityMethodInvestments	31000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Equity Method Investments DeferredTaxAssetsEquityMethodInvestments	243000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Inventory DeferredTaxAssetsInventory	240000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Inventory DeferredTaxAssetsInventory	30000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	1198000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	1289000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	5502000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards DeferredTaxAssetsTaxCreditCarryforwards	7755000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	288000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	106000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	42703000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	38235000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	1568000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	322000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	41135000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	37913000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	4421000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	6162000	USD
CY2020Q4	alrm	Deferred Tax Liabilities Operating Lease Right Of Use Assets DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets	8043000	USD
CY2019Q4	alrm	Deferred Tax Liabilities Operating Lease Right Of Use Assets DeferredTaxLiabilitiesOperatingLeaseRightOfUseAssets	7441000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	5322000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	3030000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	866000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	766000	USD
CY2020Q4	alrm	Deferred Tax Liabilities Contingent Consideration DeferredTaxLiabilitiesContingentConsideration	171000	USD
CY2019Q4	alrm	Deferred Tax Liabilities Contingent Consideration DeferredTaxLiabilitiesContingentConsideration	170000	USD
CY2020Q4	alrm	Deferred Tax Liabilities Internally Developed Software DeferredTaxLiabilitiesInternallyDevelopedSoftware	620000	USD
CY2019Q4	alrm	Deferred Tax Liabilities Internally Developed Software DeferredTaxLiabilitiesInternallyDevelopedSoftware	1208000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	19443000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	18777000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	21692000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	19136000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	3065000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2801000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1973000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1166000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	718000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	857000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	656000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	18000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	147000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	259000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	253000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2020	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	400000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	219000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	176000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	4228000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	3065000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2801000	USD
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.044
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.095
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.840
CY2020Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	100000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	200000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	4200000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	3100000	USD
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	618003000	USD
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	56298000	USD
CY2020Q4	us-gaap	Assets Assets	731687000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	502363000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	50413000	USD
CY2019Q4	us-gaap	Assets Assets	557799000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	420494000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	12202000	USD
CY2019Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	112335000	USD
CY2019Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	121660000	USD
CY2019Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	127880000	USD
CY2019Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	140488000	USD
CY2020Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	151939000	USD
CY2020Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	141637000	USD
CY2020Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	158851000	USD
CY2020Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	165576000	USD
CY2019Q1	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	38950000	USD
CY2019Q2	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	44556000	USD
CY2019Q3	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	47523000	USD
CY2019Q4	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	52570000	USD
CY2020Q1	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	57980000	USD
CY2020Q2	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	49005000	USD
CY2020Q3	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	61183000	USD
CY2020Q4	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	59260000	USD
CY2019Q1	us-gaap	Profit Loss ProfitLoss	9010000	USD
CY2019Q2	us-gaap	Profit Loss ProfitLoss	13796000	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	17690000	USD
CY2019Q4	us-gaap	Profit Loss ProfitLoss	12834000	USD
CY2020Q1	us-gaap	Profit Loss ProfitLoss	8571000	USD
CY2020Q2	us-gaap	Profit Loss ProfitLoss	16625000	USD
CY2020Q3	us-gaap	Profit Loss ProfitLoss	35825000	USD
CY2020Q4	us-gaap	Profit Loss ProfitLoss	15639000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	9010000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	13796000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	17690000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	13035000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	8807000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	16995000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	36084000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	15967000	USD
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.19
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.29
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.36
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.27
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.18
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.35
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.74
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.32
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.18
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.27
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.35
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.26
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.18
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.34
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.71
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.31

Files In Submission

Name	View Source	Status
0001459200-21-000012-index-headers.html	Edgar Link	pending
0001459200-21-000012-index.html	Edgar Link	pending
0001459200-21-000012.txt	Edgar Link	pending
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$ALRM
Alarm.com Holdings, Inc. Stock $alrm

2020 Q4 Form 10-K Financial Statement

#000145920021000012 Filed on February 25, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ALRM Alarm.com Holdings, Inc. Stock $alrm

2020 Q4 Form 10-K Financial Statement

#000145920021000012 Filed on February 25, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ALRM
Alarm.com Holdings, Inc. Stock $alrm