Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Restricted cash	$ 4,600		$ 5,000
Proceeds from sale/maturity of short-term investments	30,067	$ 49,470
Deferred income taxes assets, noncurrent	12,470		17,462
Deferred income taxes liabilities, noncurrent	4,036		$ 182
Reclassification of Debt Issuance Costs From Other Assets to Long Term Debt | ASU 2015-03
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Deferred issuance costs	5,400
Reclassification of Deferred Tax Assets Liabilities From Current to Non-Current | ASU 2015-17
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Decrease in current deferred income tax assets	18,100
Deferred income taxes assets, noncurrent	9,100
Deferred income taxes liabilities, noncurrent	$ 9,000
Maximum
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Short-term investment contractual maturities	2 years		2 years