Goodwill and Other Intangible Assets (Details 1) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Goodwill
Goodwill impairment	$ 0	$ 34,510
Accumulated goodwill impairment loss	283,100	283,100
Finite-lived intangible assets, amortization	$ 100	$ 700
Minimum
Goodwill
Finite-lived intangible asset, useful life		2 years
Maximum
Goodwill
Finite-lived intangible asset, useful life		10 years
Discount rate
Goodwill
Measurement input		0.140

Finite-lived intangible assets, amortization

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Goodwill, Measurement Input

+ References

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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.

+ References

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