Business Combinations (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Exervio [Member]
Business Acquisition [Line Items]
Date of acquisition	Apr. 01, 2011
Estimated total allocable purchase price consideration	$ 11.2
Cash paid for acquisition	6.5
Common stock issued	2.8
Fair value estimate of additional earnings-based contingent consideration	1.9
Percentage of earnings based contingent consideration paid in cash upon achievement of contingency	25.00%
Percentage of earnings based contingent consideration issued in stock upon achievement of contingency	75.00%
Transaction costs	0.6
JCB [Member]
Business Acquisition [Line Items]
Date of acquisition	Jul. 01, 2011
Estimated total allocable purchase price consideration	16.6
Cash paid for acquisition	12.5
Common stock issued	4.1
Transaction costs	0.6
PointBridge [Member]
Business Acquisition [Line Items]
Date of acquisition	Feb. 08, 2012
Estimated total allocable purchase price consideration	20.5
Cash paid for acquisition	14.4
Common stock issued	6.1
Transaction costs	0.7
Nascent [Member]
Business Acquisition [Line Items]
Date of acquisition	Jun. 01, 2012
Estimated total allocable purchase price consideration	16.5
Cash paid for acquisition	11.3
Common stock issued	5.2
Transaction costs	0.6
Northridge [Member]
Business Acquisition [Line Items]
Date of acquisition	Jul. 01, 2012
Estimated total allocable purchase price consideration	13.9
Cash paid for acquisition	10.7
Common stock issued	3.2
Transaction costs	$ 0.6
Minimum [Member] | Exervio [Member]
Business Acquisition [Line Items]
Intangible assets estimated useful life	9 months
Minimum [Member] | JCB [Member]
Business Acquisition [Line Items]
Intangible assets estimated useful life	6 months
Minimum [Member] | PointBridge [Member]
Business Acquisition [Line Items]
Intangible assets estimated useful life	11 months
Minimum [Member] | Nascent [Member]
Business Acquisition [Line Items]
Intangible assets estimated useful life	7 months
Minimum [Member] | Northridge [Member]
Business Acquisition [Line Items]
Intangible assets estimated useful life	9 months
Maximum [Member] | Exervio [Member]
Business Acquisition [Line Items]
Intangible assets estimated useful life	7 years
Maximum [Member] | JCB [Member]
Business Acquisition [Line Items]
Intangible assets estimated useful life	5 years
Maximum [Member] | PointBridge [Member]
Business Acquisition [Line Items]
Intangible assets estimated useful life	5 years
Maximum [Member] | Nascent [Member]
Business Acquisition [Line Items]
Intangible assets estimated useful life	5 years
Maximum [Member] | Northridge [Member]
Business Acquisition [Line Items]
Intangible assets estimated useful life	5 years