v3.21.2

Summary of Significant Accounting Policies - Deferred Implementation Costs, Deferred Solution and Other Costs (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Deferred Implementation Costs |  |  |  |
Capitalized Contract Cost [Line Items] |  |  |  |
Capitalization of implementation costs | $ 3.4 | $ 4.9 | $ 10.3 | $ 13.9
Amortization of capitalized implementation costs | $ 2.8 | 3.3 | $ 7.9 | 7.8
Deferred Implementation Costs | Minimum |  |  |  |
Capitalized Contract Cost [Line Items] |  |  |  |
Expected period of customer benefit | 5 years |  | 5 years |
Deferred Implementation Costs | Maximum |  |  |  |
Capitalized Contract Cost [Line Items] |  |  |  |
Expected period of customer benefit | 7 years |  | 7 years |
Deferred Commissions |  |  |  |
Capitalized Contract Cost [Line Items] |  |  |  |
Capitalization of implementation costs | $ 1.7 | 4.0 | $ 8.1 | 12.5
Amortization of capitalized implementation costs | $ 3.0 | $ 2.1 | $ 9.5 | $ 6.1
Deferred Commissions | Minimum |  |  |  |
Capitalized Contract Cost [Line Items] |  |  |  |
Expected period of customer benefit | 5 years |  | 5 years |
Deferred Commissions | Maximum |  |  |  |
Capitalized Contract Cost [Line Items] |  |  |  |
Expected period of customer benefit | 7 years |  | 7 years |

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- Definition Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123353750&loc=SL49131252-203054 + Details
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- Definition Amortization period of cost capitalized in obtaining or fulfilling contract with customer, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123353750&loc=SL49131251-203054 + Details
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