Summary of Significant Accounting Policies Intangible Assets (Details)	12 Months Ended
	Dec. 31, 2014
Intangible Assets
Impairment Indicators, Long-Lived Assets	0
Technology-Based Intangible Assets [Member]
Intangible Assets
Estimated useful lives of the assets	3 years
Customer Relationships [Member]
Intangible Assets
Estimated useful lives of the assets	10 years
Customer Relationships [Member] | Minimum [Member]
Intangible Assets
Estimated useful lives of the assets	5 years
Customer Relationships [Member] | Maximum [Member]
Intangible Assets
Estimated useful lives of the assets	10 years
Developed product technologies [Member]
Intangible Assets
Estimated useful lives of the assets	3 years
Trademarks [Member] | Minimum [Member]
Intangible Assets
Estimated useful lives of the assets	3 years
Trademarks [Member] | Maximum [Member]
Intangible Assets
Estimated useful lives of the assets	5 years
Covenants not to compete [Member] | Minimum [Member]
Intangible Assets
Estimated useful lives of the assets	2 years
Covenants not to compete [Member] | Maximum [Member]
Intangible Assets
Estimated useful lives of the assets	4 years