Nature of Operations and Summary of Significant Accounting Policies - Intangible Assets (Details)	12 Months Ended
Dec. 31, 2017
Minimum
Intangible Assets [Abstract]
Estimated useful lives of intangible assets	2 years
Maximum
Intangible Assets [Abstract]
Estimated useful lives of intangible assets	20 years

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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