Summary of Significant Accounting Policies (Details Textuals) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Summary of Significant Accounting Policies (Textuals) [Abstract]
Amortization expense	$ 3.7	$ 3.5	$ 7.4	$ 7.1
Future Amortization Expense Current Year			15.1
Aggregate amortization expense for 2020	15.4		15.4
Aggregate amortization expense for 2021	14.1		14.1
Aggregate amortization expense for 2023	12.7		12.7
Aggregate amortization expense for 2024	13.3		13.3
Aggregate amortization expense for 2025	11.7		11.7
Purchased Intangible Amortization, Gross	3.5	3.3	6.9	6.7
Purchased intangible amortization, net of tax	2.6	2.5	5.2	5.0
Amortization expense associated with capitalized software	8.5	8.4	17.0	16.5
Share - based compensation expense	$ 4.3	$ 3.9	$ 8.8	$ 8.2

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

No definition available.

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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 expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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