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Short-Term And Long-Term Investments And Restricted Deposits (Short-Term And Long-Term Investments And Restricted Deposits By Investment Type) (Details) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
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Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | $ 945,129 | $ 718,811
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 4,788 | 8,833
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | (8,945) | (487)
Fair Value | 940,972 | 727,157
Mortgage-backed Securities Available-for-sale, Fair Value Disclosure | 33,891 | 0
U.S. Treasury Securities And Obligations Of U.S. Government Corporations And Agencies [Member] |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 246,085 | 110,941
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 245 | 581
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | (7,494) | (221)
Fair Value | 238,836 | 111,301
Corporate Securities [Member] |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 293,912 | 290,691
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 2,782 | 4,615
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | (608) | (195)
Fair Value | 296,086 | 295,111
Restricted Certificates Of Deposit [Member] |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 5,891 | 5,890
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 0 | 0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | 0 | 0
Fair Value | 5,891 | 5,890
Restricted Cash Equivalents [Member] |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 26,642 | 14,455
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 0 | 0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | 0 | 0
Fair Value | 26,642 | 14,455
Municipal Securities, General Obligation [Member] |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 54,003 | 85,440
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 555 | 1,157
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | (136) | (26)
Fair Value | 54,422 | 86,571
Municipal Securities, Pre-Refunded [Member] |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 10,835 | 5,337
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 82 | 85
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | 0 | 0
Fair Value | 10,917 | 5,422
Municipal Securities, Revenue [Member] |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 68,801 | 82,781
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 545 | 1,313
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | (292) | (30)
Fair Value | 69,054 | 84,064
Municipal Securities, Variable Rate Demand Notes [Member] |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 28,575 | 23,385
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 0 | 0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | 0 | 0
Fair Value | 28,575 | 23,385
Asset Backed Securities [Member] |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 138,803 | 73,570
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 579 | 1,082
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | (332) | (15)
Fair Value | 139,050 | 74,637
Mortgage backed securities |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 33,974 | 0
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 0 | 0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | (83) | 0
Fair Value | 33,891 | 0
Cost And Equity Method Investments [Member] |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 22,239 | 11,298
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 0 | 0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | 0 | 0
Fair Value | 22,239 | 11,298
Life Insurance Contracts [Member] |  |
Schedule Of Investments And Restricted Deposits By Type [Line Items] |  |
Amortized Cost | 15,369 | 15,023
Available For Sale Securities Gross Unrealized Gain Accumulated In Investments | 0 | 0
Available For Sale Securities Gross Unrealized Loss Accumulated In Investments | 0 | 0
Fair Value | $ 15,369 | $ 15,023

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Mortgage-Backed Securities -URI http://asc.fasb.org/extlink&oid=6517959 + Details
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