Goodwill and Intangible Assets - Finite-lived Intangible Assets Roll Forward (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Finite-lived Intangible Assets, Gross [Roll Forward]
Intangible assets, January 1	$ 7,602	$ 7,602
Additions	0	0
Total intangible assets, end of period	7,602	7,602
Accumulated amortization
Accumulated amortization	(7,515)	(7,404)
Current year amortization	(28)us-gaap_AmortizationOfIntangibleAssets	(28)us-gaap_AmortizationOfIntangibleAssets
Total accumulated amortization	(7,543)	(7,432)
Net intangible assets, end of period	$ 59us-gaap_FiniteLivedIntangibleAssetsNet	$ 170us-gaap_FiniteLivedIntangibleAssetsNet

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, resulting from a business combination.

+ References

No definition available.

+ Details

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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