Goodwill and Other Intangible Assets (Schedule of Intangible Assets and Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Other intangible assets
Gross amount, End of Period	$ 58,399	$ 58,477
Accumulated impairment losses and amortization, End of Period	(43,424)	(39,560)
Other intangible assets, Net, End of Period	14,975	18,917
Goodwill and Other intangible assets, Total
Goodwill and Other intangible assets, Net, End of Period	7,902	8,111
Excluding Equity Method Investments
Goodwill
Goodwill, Gross amount, Beginning of Period	8,160	8,160
Accumulated impairment losses and amortization, Beginning of Period	(2,299)	(2,299)
Goodwill, Net, Beginning of Period	5,861	5,861
Goodwill, Gross amount, End of Period	8,160	8,160
Accumulated impairment losses and amortization, End of Period	(2,299)	(2,299)
Goodwill, Net, End of Period	5,861	5,861
Other intangible assets
Gross amount, Beginning of Period	12,999	12,999
Accumulated impairment losses and amortization, Beginning of Period	(10,749)	(10,374)
Other intangible assets, Net, Beginning of Period	2,250	2,625
Amortization	(209)	(375)
Gross amount, End of Period	12,999	12,999
Accumulated impairment losses and amortization, End of Period	(10,958)	(10,749)
Other intangible assets, Net, End of Period	2,041	2,250
Goodwill and Other intangible assets, Total
Gross amount, Beginning of Period	21,159	21,159
Accumulated impairment losses and amortization, Beginning of Period	(13,048)	(12,673)
Goodwill and Other intangible assets, Net, Beginning of Period	8,111	8,486
Amortization	(209)	(375)
Gross amount, End of Period	21,159	21,159
Accumulated impairment losses and amortization, End of Period	(13,257)	(13,048)
Goodwill and Other intangible assets, Net, End of Period	$ 7,902	$ 8,111

Goodwill and Intangible Assets, Accumulated Impairment and Amortization

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Goodwill and Intangible Assets, Gross

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Intangible Assets (Excluding Goodwill), Accumulated Amortization and Impairment

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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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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 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.

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Amount before 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.

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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.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance.

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