Balance Sheet Components (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Balance Sheet Components [Line Items]
Goodwill, Impaired, Accumulated Impairment Loss	$ 74,200,000	$ 74,200,000
Cost method investment	105,000	1,322,000
Cost-method Investments, Other than Temporary Impairment	0	0	$ 0
Amortization expense	17,300,000	17,900,000	15,500,000
Goodwill impairment charges	0	74,196,000	0
Intangibles Impairment charges	$ 0	0	$ 2,000,000
Minimum [Member]
Balance Sheet Components [Line Items]
Available-for-sale Securities, Maturity Period ( in months)	3 months
Maximum [Member]
Balance Sheet Components [Line Items]
Available-for-sale Securities, Maturity Period ( in months)	12 months
Service Provider [Member]
Balance Sheet Components [Line Items]
Goodwill impairment charges	$ 0	$ 74,196,000