Summary of Significant Accounting Policies (Details Textuals) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Summary of Significant Accounting Policies (Textuals) [Abstract]
Amortization expense	$ 4.1	$ 3.9
Future Amortization Expense Current Year	21.6
Aggregate amortization expense for 2020	21.1
Aggregate amortization expense for 2021	20.3
Aggregate amortization expense for 2022	19.8
Aggregate amortization expense for 2023	18.8
Aggregate amortization expense for 2024	16.6
Purchased Intangible Amortization, Gross	3.8		$ 3.7
Purchased intangible amortization, net of tax	2.9		$ 2.8
Amortization expense associated with capitalized software	9.8	10.0
Share - based compensation expense	$ 4.6	$ 4.4

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.

+ References

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

+ References

No definition available.

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Summary of Significant Accounting Policies.

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No definition available.

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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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