Description of Business and Summary of Significant Accounting Policies (Intangible Assets) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	$ 0	$ 0	$ 0
Finite-Lived Intangible Assets, Gross	95,220,000	86,301,000
Finite-lived intangible assets, accumulated amortization	(43,372,000)	(36,930,000)
Estimated future amortization expense	51,848,000	49,371,000
Goodwill, Impairment Loss	0	0	$ 0
Customer Relationships
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-Lived Intangible Assets, Gross	$ 76,275,000	66,783,000
Customer Relationships | Minimum [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-lived intangible asset, useful life	7 years
Customer Relationships | Maximum [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-lived intangible asset, useful life	20 years
Developed Technology
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-Lived Intangible Assets, Gross	$ 15,121,000	15,664,000
Developed Technology | Minimum [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-lived intangible asset, useful life	3 years
Developed Technology | Maximum [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-lived intangible asset, useful life	12 years
Trademarks
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-Lived Intangible Assets, Gross	$ 2,729,000	2,751,000
Trademarks | Minimum [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-lived intangible asset, useful life	3 years
Trademarks | Maximum [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-lived intangible asset, useful life	15 years
Noncompete Agreements
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-Lived Intangible Assets, Gross	$ 743,000	751,000
Noncompete Agreements | Maximum [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-lived intangible asset, useful life	5 years
Backlog
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-Lived Intangible Assets, Gross	$ 140,000	140,000
Database
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-Lived Intangible Assets, Gross	$ 212,000	212,000
Database | Maximum [Member]
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Finite-lived intangible asset, useful life	10 years
Customer Relationships
Finite-Lived and Indefinite-Lived Intangible Assets [Line items]
Indefinite-lived intangible assets	$ 30,887,000	$ 30,887,000