Summary of Significant Accounting Policies (Details Textuals) - USD ($) shares in Thousands, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	May 06, 2021
Summary of Significant Accounting Policies (Textuals) [Abstract]
Amortization expense	$ 6.2	$ 3.9	$ 10.2	$ 7.9
Future Amortization Expense Current Year			21.6
Aggregate amortization expense for 2020	21.1		21.1
Aggregate amortization expense for 2021	20.4		20.4
Aggregate amortization expense for 2023	19.8		19.8
Aggregate amortization expense for 2024	18.9		18.9
Aggregate amortization expense for 2025	16.6		16.6
Purchased Intangible Amortization, Gross	5.9	3.7	9.7	7.5
Purchased intangible amortization, net of tax	4.5	2.8	7.3	5.6
Amortization expense associated with capitalized software	10.0	9.9	19.8	19.9
Share - based compensation expense	$ 4.6	$ 4.4	$ 9.2	$ 8.8
Additional Shares Issued under Equity Incentive Plan					900
Shares Remaining Under Equity Incentive Plan Prior to Amendment					2,100

Additional Shares Issued under Equity Incentive Plan (Amended and Restated)

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The aggregate expense charged against earnings to amortize the cost of acquired intangible assets.

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The amount of amortization expense expected to be recognized during the current year.

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The aggregate expense charged against earnings to amortize the cost of acquired intangible assets before tax.

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Shares Remaining Under Equity Incentive Plan Prior to Amendment

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Summary of Significant Accounting Policies.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. 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 expense for amortization of capitalized computer software costs.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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