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Short-Term And Long-Term Investments And Restricted Deposits (Contractual Maturities Of Short-Term And Long-Term Investments And Restricted Deposits) (Details) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
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Investments [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
One year or less, Amortized Cost | $ 101,537 | $ 136,997
One year through five years, Amortized Cost | 609,755 | 429,053
Five years through ten years, Amortized Cost | 157,003 | 93,907
Greater than ten years, Amortized Cost | 29,900 | 24,599
Total, Amortized Cost | 898,195 | 684,556
One year or less, Fair Value | 102,126 | 138,101
One year through five years, Fair Value | 610,589 | 435,728
Five years through ten years, Fair Value | 151,221 | 93,778
Greater than ten years, Fair Value | 30,090 | 25,264
Total, Fair Value | 894,026 | 692,871
Restricted Deposits [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
One year or less, Amortized Cost | 40,633 | 33,897
One year through five years, Amortized Cost | 6,301 | 358
Five years through ten years, Amortized Cost | 0 | 0
Greater than ten years, Amortized Cost | 0 | 0
Total, Amortized Cost | 46,934 | 34,255
One year or less, Fair Value | 40,637 | 33,928
One year through five years, Fair Value | 6,309 | 358
Five years through ten years, Fair Value | 0 | 0
Greater than ten years, Fair Value | 0 | 0
Total, Fair Value | $ 46,946 | $ 34,286

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