Description of contracts with customer.

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Description of sales commission plan.

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Line items for revenue recognition and sales commissions.

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Sales commissions, amortization term description.

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Term of contracts with customer.

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The amount of expense recognized in the current period for the periodic realization of capitalized fees that were paid to salespeople, distributors, brokers, and agents at the time of the conclusion of the sale. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Revenue Recognition and Sales Commissions - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenue Recognition and Sales Commissions [Line Items]
Revenue recognized in period, included in deferred revenue at beginning of the period	$ 33,800,000	$ 32,400,000	$ 61,300,000	$ 59,000,000.0
Estimated revenue expected to be recognized in future under contract with customers	420,000,000		$ 420,000,000
Description of sales commission plan			Sales commissions earned by our sales force are considered incremental and recoverable costs of obtaining a contract with a customer. The Company’s sales commission plans for 2018 and 2019 typically include multiple payments, including initial payments in the period a customer contract is obtained and subsequent payments either 15 or 27 months after the initial payment.
Sales Commissions, amortization term description			Non-commensurate commissions are amortized over the greater of the expected period of benefit or technological obsolescence period.
Amortization of deferred commissions	2,100,000	2,000,000.0	$ 6,269,000	5,695,000
Customer Contracts [Member]
Revenue Recognition and Sales Commissions [Line Items]
Impairment losses on receivables and contract asset	$ 51,000	$ 300,000	$ 99,000	$ 690,000
Subscription SaaS Services [Member]
Revenue Recognition and Sales Commissions [Line Items]
Description of contracts with customer			Subscription/SaaS contracts are generally non-cancelable, one to five years in length, and billed annually, semi-annually, quarterly, or monthly in advance.
Subscription SaaS Services [Member] \| Minimum [Member]
Revenue Recognition and Sales Commissions [Line Items]
Period of contract with customer			1 year
Subscription SaaS Services [Member] \| Maximum [Member]
Revenue Recognition and Sales Commissions [Line Items]
Period of contract with customer			5 years