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Payments to Acquire Businesses, Cash Portion

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Share-based Compensation Arrangement by Share-based Payment Award, Converted During Period

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Share-based Compensation Arrangement by Share-based Payment Award, Nonvested, Fair Value

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed in Period, Gross

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete.

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- Definition

Amount of deferred tax asset attributable to deductible temporary differences and carryforwards acquired at the acquisition date.

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

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Unrecognized cost of unvested options awarded to employees as compensation.

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The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Acquisitions - Connect and Piper Business Units from Icontrol Networks, Inc. (Details) $ in Thousands			3 Months Ended	12 Months Ended
	Mar. 08, 2017 USD ($) business_unit shares	Mar. 07, 2017 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Business Acquisition [Line Items]
Amounts drawn under senior line of credit				$ 0	$ 139,000	$ 0
Assumed options from business acquisition				0	1,375	0
Compensation cost not yet recognized on nonvested awards				4,600
Goodwill				63,591	$ 63,591	$ 24,723
Connect And Piper
Business Acquisition [Line Items]
Number of business units acquired \| business_unit	2
Cash paid to acquire business	$ 148,500
Amount deposited in escrow	14,500
Cash portion	81,500
Amounts drawn under senior line of credit		$ 67,000
Assumed options from business acquisition	1,375
Goodwill	$ 36,610
Increase to intangible assets			$ 100
Decrease in goodwill due to working capital adjustment			$ (100)
Connect
Business Acquisition [Line Items]
Unvested employee stock options converted during period (in shares) \| shares	2,001,387
Options assumed in period (in shares) \| shares	70,406
Fair value of unvested stock options	$ 1,700
Assumed options from business acquisition	1,400
Compensation cost not yet recognized on nonvested awards				$ 100
Piper
Business Acquisition [Line Items]
Deferred tax asset	4,100
Customer Relationships Group 1 \| Connect
Business Acquisition [Line Items]
Intangible assets acquired	$ 92,500
Weighted-average estimated useful life of intangible assets acquired (years)	12 years
Customer Relationships Group 2 \| Connect
Business Acquisition [Line Items]
Intangible assets acquired	$ 800
Weighted-average estimated useful life of intangible assets acquired (years)	4 years
Developed Technology \| Connect And Piper
Business Acquisition [Line Items]
Intangible assets acquired	$ 4,770
Developed Technology \| Connect
Business Acquisition [Line Items]
Intangible assets acquired	$ 4,400
Weighted-average estimated useful life of intangible assets acquired (years)	3 years
Developed Technology \| Piper
Business Acquisition [Line Items]
Intangible assets acquired	$ 300
Trade Name \| Connect And Piper
Business Acquisition [Line Items]
Intangible assets acquired	170
Trade Name \| Piper
Business Acquisition [Line Items]
Intangible assets acquired	$ 200
Weighted-average estimated useful life of intangible assets acquired (years)	3 years
Share-based Compensation Award, Tranche One \| Connect
Business Acquisition [Line Items]
Compensation cost not yet recognized on nonvested awards	$ 300