Quarterly report pursuant to Section 13 or 15(d)

Short-Term And Long-Term Investments And Restricted Deposits (Fair Value Of Available-For-Sale Investments With Gross Unrealized Losses By Investment Type And Length Of Time) (Details)

v2.4.0.8
Short-Term And Long-Term Investments And Restricted Deposits (Fair Value Of Available-For-Sale Investments With Gross Unrealized Losses By Investment Type And Length Of Time) (Details) (USD $)
In Thousands, unless otherwise specified
Jun. 30, 2014
Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]    
Less Than 12 Months, Fair Value $ 79,333 $ 327,939
Available For Sale Securities Continuous Unrealized Loss Position 12 Months Or Longer Aggregate Losses Accumulated In Investments 3,478 1,577
12 Months or More, Fair Value 202,685 33,900
Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses Accumulated In Investments (180) (7,368)
U.S. Treasury Securities And Obligations Of U.S. Government Corporations And Agencies [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Less Than 12 Months, Fair Value 11,987 172,365
Available For Sale Securities Continuous Unrealized Loss Position 12 Months Or Longer Aggregate Losses Accumulated In Investments 3,331 1,307
12 Months or More, Fair Value 179,105 26,454
Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses Accumulated In Investments (18) (6,188)
Corporate Securities [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Less Than 12 Months, Fair Value 56,343 52,725
Available For Sale Securities Continuous Unrealized Loss Position 12 Months Or Longer Aggregate Losses Accumulated In Investments 17 207
12 Months or More, Fair Value 985 5,020
Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses Accumulated In Investments (149) (400)
Municipal Securities, General Obligation [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Less Than 12 Months, Fair Value 0 3,480
Available For Sale Securities Continuous Unrealized Loss Position 12 Months Or Longer Aggregate Losses Accumulated In Investments 22 63
12 Months or More, Fair Value 3,476 2,426
Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses Accumulated In Investments 0 (72)
Municipal Securities, Pre-Refunded [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Less Than 12 Months, Fair Value 1,034 0
Available For Sale Securities Continuous Unrealized Loss Position 12 Months Or Longer Aggregate Losses Accumulated In Investments 0 0
12 Months or More, Fair Value 0 0
Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses Accumulated In Investments (10) 0
Municipal Securities, Revenue [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Less Than 12 Months, Fair Value 0 27,789
Available For Sale Securities Continuous Unrealized Loss Position 12 Months Or Longer Aggregate Losses Accumulated In Investments 42 0
12 Months or More, Fair Value 3,413 0
Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses Accumulated In Investments 0 (292)
Asset Backed Securities [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Less Than 12 Months, Fair Value 0 37,689
Available For Sale Securities Continuous Unrealized Loss Position 12 Months Or Longer Aggregate Losses Accumulated In Investments 0 0
12 Months or More, Fair Value 0 0
Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses Accumulated In Investments 0 (333)
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
   
Schedule of Available-for-sale Securities [Line Items]    
Less Than 12 Months, Fair Value 9,969 33,891
Available For Sale Securities Continuous Unrealized Loss Position 12 Months Or Longer Aggregate Losses Accumulated In Investments 66 0
12 Months or More, Fair Value 15,706 0
Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses Accumulated In Investments $ (3) $ (83)