Intangible Assets and Goodwill (Rollforward) (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Goodwill | |||
| Balance at beginning of period | $ 239,263 | $ 239,263 | |
| Additions from acquisitions | 3,001 | ||
| Balance at end of period | 242,264 | 239,263 | $ 239,263 |
| Other Intangible Assets | |||
| Balance at beginning of period | 74,444 | 69,290 | |
| Additions from acquisitions | 2,943 | ||
| Asset additions | 11,546 | 17,601 | |
| Amortization expense | (13,164) | (12,447) | (10,442) |
| Asset deletions | (72) | ||
| Balance at end of period | $ 75,697 | $ 74,444 | $ 69,290 |
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- Definition Finite-Lived Intangible Assets Acquired From Asset Acquisition No definition available.
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- Definition Finite-Lived Intangible Assets Disposed Of No definition available.
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition. No definition available.
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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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