[Line Items] for Accounting Policies [Table]

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Capitalized Contract Cost, Net

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Contract Termination Requirement, Period of Notification

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Depreciation and Amortization Expense

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Revenue Recognition, Multiple-deliverable Arrangements, Determination of Vendor-Specific Objective Evidence (VSOE), Minimum Percent of Sales

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Revenue Recognition, Multiple-deliverable Arrangements, Vendor-Specific Objective Evidence, Percent of Selling Price

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Revenue from Contract with Customer, Excluding Assessed Tax

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Transfer of Financial Assets Accounted for as Sales, Receivable from Third-Party Leasing Company, Amount

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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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Amount of expense for administrative services provided to the limited liability company (LLC) or limited partnership (LP) by the managing member or general partner, affiliate of managing member or general partner, or affiliate of LLC or LP, for example, but not limited to, salaries, rent, or overhead costs.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of increase (decrease) in capitalized computer software costs.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of the effect of a change in accounting principle on net income.

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Payments of cash to suppliers for goods and services during the current period.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

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Primarily represents commissions incurred in the period based upon the sale by commissioned employees or third parties of the entity's goods or services, and fees for sales assistance or product enhancements performed by third parties (such as a distributor or value added reseller).

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Cost incurred during the reporting period in transporting goods and services to customers. Includes freight-out costs.

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Fair value of derecognized financial assets from transactions which comprise an initial transfer and an agreement entered into in contemplation of the initial transfer resulting in retention of substantially all of the exposure to the economic return throughout the term of the transaction.

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Organization and Summary of Significant Accounting Policies (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Mar. 31, 2017	Apr. 30, 2015
Accounting Policies [Line Items]
Vendor-Specific Objective Evidence (VSOE) exist when (approximately 80% or more) standalone sales are within a reasonable price range		80.00%
Transferred non-recourse accounts receivables		$ 40,000,000	$ 28,700,000	$ 38,600,000
Accounts receivables from third-party leasing companies for transferred non-recourse accounts receivables		100,000	200,000	800,000
Depreciation and amortization		16,200,000	15,000,000	12,800,000
Commissions expense		19,400,000	22,000,000	13,700,000
Administrative fees		7,400,000	8,400,000	5,900,000
Cumulative effect of a change in accounting principle related to stock-based compensation		1,582,000
Accumulated Earnings (Deficit)
Accounting Policies [Line Items]
Cumulative effect of a change in accounting principle related to stock-based compensation		1,582,000
ASU 2016-09
Accounting Policies [Line Items]
Change in accounting guidance, impact on net income	$ 6,600,000
ASU 2016-09 \| Accumulated Earnings (Deficit)
Accounting Policies [Line Items]
Cumulative effect of a change in accounting principle related to stock-based compensation					$ 1,600,000
ASU 2014-09 \| Difference between Revenue Guidance in Effect before andafter Topic 606 \| Pro Forma \| Accumulated Earnings (Deficit)
Accounting Policies [Line Items]
Software revenue		$ (3,000,000)	2,000,000
Internal use software and development costs
Accounting Policies [Line Items]
Useful life (in years)		5 years
Software and development costs to be sold
Accounting Policies [Line Items]
Cost of revenues for amortization of capitalized software development cost		$ 9,700,000	7,100,000	5,800,000
Minimum
Accounting Policies [Line Items]
Vendor-Specific Objective Evidence, within a reasonably narrow price range (plus or minus of median rate)		15.00%
Estimated useful lives of assets (in years)		1 year
Minimum \| ASU 2014-09 \| Difference between Revenue Guidance in Effect before andafter Topic 606 \| Pro Forma \| Accumulated Earnings (Deficit)
Accounting Policies [Line Items]
Capitalized commissions		$ 19,000,000
Minimum \| Computer Equipment
Accounting Policies [Line Items]
Useful life (in years)		3 years
Minimum \| Furniture and Fixtures
Accounting Policies [Line Items]
Useful life (in years)		5 years
Minimum \| Equipment
Accounting Policies [Line Items]
Useful life (in years)		3 years
Maximum
Accounting Policies [Line Items]
Vendor-Specific Objective Evidence, within a reasonably narrow price range (plus or minus of median rate)		15.00%
Estimated useful lives of assets (in years)		30 years
Maximum \| ASU 2014-09 \| Difference between Revenue Guidance in Effect before andafter Topic 606 \| Pro Forma \| Accumulated Earnings (Deficit)
Accounting Policies [Line Items]
Capitalized commissions		$ 20,000,000
Maximum \| Computer Equipment
Accounting Policies [Line Items]
Useful life (in years)		5 years
Maximum \| Furniture and Fixtures
Accounting Policies [Line Items]
Useful life (in years)		7 years
Maximum \| Equipment
Accounting Policies [Line Items]
Useful life (in years)		12 years
Selling, general and administrative
Accounting Policies [Line Items]
Shipping and handling expenses		$ 13,600,000	12,100,000	8,500,000
Capitalized software costs included in property and equipment \| Internal use software and development costs
Accounting Policies [Line Items]
Software development costs capitalized		400,000	2,200,000
Capitalized software costs included in other assets \| Software and development costs to be sold
Accounting Policies [Line Items]
Software development costs capitalized		15,000,000	14,300,000
Primary Supplier
Accounting Policies [Line Items]
Minimum supplier purchase obligations		$ 0
Notice of termination, time upon delivery (in months)		2 months
Payments to suppliers		$ 64,500,000	$ 47,900,000	$ 41,700,000
Credit Concentration Risk \| Lease Receivable
Accounting Policies [Line Items]
Concentration risk percentage		33.00%
Customer Concentration Risk
Accounting Policies [Line Items]
Concentration risk percentage		51.20%	51.20%	65.20%
Customer Concentration Risk \| Sales Revenue, Net
Accounting Policies [Line Items]
Concentration risk percentage		51.20%
Avantec Heathcare Limited
Accounting Policies [Line Items]
Percentage of interest acquired						85.00%
Revolving Credit Facility
Accounting Policies [Line Items]
Debt instrument, term (in years)		5 years
Term Loan Facility
Accounting Policies [Line Items]
Debt instrument, term (in years)		5 years