Summary of Significant Accounting Policies (Details Textual) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	$ 4,300	$ 5,000
Proceeds from sale/maturity of short-term investments	157,825	192,994	$ 197,466
Research and development	$ 98,683	101,950	$ 104,712
Repurchase of common stock, shares	0.3
ASU 2015-03
Summary Of Significant Accounting Policies [Line Items]
Deferred issuance costs		5,400
ASU 2015-17 | Decrease in Deferred Tax Assets Current
Summary Of Significant Accounting Policies [Line Items]
Prior period reclassification adjustment		18,100
ASU 2015-17 | Increase in Deferred Tax Assets Noncurrent
Summary Of Significant Accounting Policies [Line Items]
Prior period reclassification adjustment		9,100
ASU 2015-17 | Decrease in Deferred Tax Liabilities Noncurrent
Summary Of Significant Accounting Policies [Line Items]
Prior period reclassification adjustment		$ 9,000
Common stock Warrants
Summary Of Significant Accounting Policies [Line Items]
Common stock warrants issued, per warrant	$ 26.68
Minimum
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, useful lives	3 years
Minimum | Cloud and Related Solutions Revenue
Summary Of Significant Accounting Policies [Line Items]
Long-term arrangements service period	3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Short-term investment contractual maturities	2 years	2 years
Property and equipment, useful lives	10 years
Maximum | Cloud and Related Solutions Revenue
Summary Of Significant Accounting Policies [Line Items]
Long-term arrangements service period	5 years