Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation and Accounting Policy (Deferred Revenues Included In Other Current Liabilities) (Details)

v2.4.1.9
Basis of Presentation and Accounting Policy (Deferred Revenues Included In Other Current Liabilities) (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Movement in Deferred Revenue [Roll Forward]    
Balance at beginning of period $ 31,047us-gaap_DeferredRevenue $ 24,243us-gaap_DeferredRevenue
Revenues deferred during the period 7,829us-gaap_DeferredRevenueAdditions 8,344us-gaap_DeferredRevenueAdditions
Revenues recognized during the period (6,210)us-gaap_DeferredRevenueRevenueRecognized (6,118)us-gaap_DeferredRevenueRevenueRecognized
Balance at end of period $ 32,666us-gaap_DeferredRevenue $ 26,469us-gaap_DeferredRevenue