XML 30 R78.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Fair Value of Plan Assets (Details) (USD $) In Thousands, unless otherwise specified |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12 Months Ended |  | 12 Months Ended |  |  |  |  |  |
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Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2011 Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2009 Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Pension Plans, Defined Benefit [Member] | Dec. 31, 2009 Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Cash and Cash Equivalents [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Cash and Cash Equivalents [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Cash and Cash Equivalents [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Cash and Cash Equivalents [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Equity Securities of U.S. Companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Equity Securities of U.S. Companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Equity Securities of U.S. Companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Equity Securities of U.S. Companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Equities Securities of International companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Equities Securities of International companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Equities Securities of International companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Equities Securities of International companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Insurance Investment Contract [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Insurance Investment Contract [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Collective and Mutual funds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Collective and Mutual funds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Corporate Debt Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Corporate Debt Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Collateral held on loaned securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Collateralized Mortgage Backed Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Collateralized Mortgage Backed Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Municipal Bonds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Municipal Bonds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 US Treasury Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 US Treasury Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Cash and Cash Equivalents [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Cash and Cash Equivalents [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Cash and Cash Equivalents [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Cash and Cash Equivalents [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Equity Securities of U.S. Companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Equity Securities of U.S. Companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Equity Securities of U.S. Companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Equity Securities of U.S. Companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Equities Securities of International companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Equities Securities of International companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Equities Securities of International companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Equities Securities of International companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Insurance Investment Contract [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Insurance Investment Contract [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Collective and Mutual funds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Collective and Mutual funds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Corporate Debt Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Corporate Debt Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Collateral held on loaned securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Collateralized Mortgage Backed Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Collateralized Mortgage Backed Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] Municipal Bonds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] Municipal Bonds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 1 [Member] US Treasury Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 1 [Member] US Treasury Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Cash and Cash Equivalents [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Cash and Cash Equivalents [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Cash and Cash Equivalents [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Cash and Cash Equivalents [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Equity Securities of U.S. Companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Equity Securities of U.S. Companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Equity Securities of U.S. Companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Equity Securities of U.S. Companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Equities Securities of International companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Equities Securities of International companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Equities Securities of International companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Equities Securities of International companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Insurance Investment Contract [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Insurance Investment Contract [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Collective and Mutual funds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Collective and Mutual funds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Corporate Debt Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Corporate Debt Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Collateral held on loaned securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Collateralized Mortgage Backed Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Collateralized Mortgage Backed Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Municipal Bonds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] Municipal Bonds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] US Treasury Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 2 [Member] US Treasury Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Cash and Cash Equivalents [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Cash and Cash Equivalents [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Cash and Cash Equivalents [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Cash and Cash Equivalents [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Equity Securities of U.S. Companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Equity Securities of U.S. Companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Equity Securities of U.S. Companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Equity Securities of U.S. Companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Equities Securities of International companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Equities Securities of International companies [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Equities Securities of International companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Equities Securities of International companies [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Insurance Investment Contract [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Insurance Investment Contract [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Collective and Mutual funds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Collective and Mutual funds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Corporate Debt Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Corporate Debt Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Collateral held on loaned securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Collateral held on loaned securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Collateralized Mortgage Backed Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Collateralized Mortgage Backed Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Municipal Bonds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] Municipal Bonds [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] US Treasury Securities [Member] Pension Plans, Defined Benefit [Member] | Dec. 31, 2010 Fair Value, Inputs, Level 3 [Member] US Treasury Securities [Member] Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of Investment Managers of the Plan Assets |  |  | 1 |  |  | 12 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Before Obligations For Collateral Received |  |  |  |  |  |  | $ 303,292 |  |  |  |  | $ 13,362 |  |  |  | $ 102,944 |  |  |  | $ 40,017 |  |  |  |  |  |  | $ 63,111 | [1] |  | $ 23,014 | $ 23,842 | [2] |  | $ 19,478 |  | $ 8,285 |  | $ 9,239 |  |  |  | $ 193,034 |  |  |  | $ 4,663 |  |  |  | $ 102,944 |  |  |  | $ 40,017 |  |  |  |  |  |  | $ 45,410 | [1] |  | $ 0 | $ 0 | [2] |  | $ 0 |  | $ 0 |  | $ 0 |  |  |  | $ 109,564 |  |  |  | $ 8,699 |  |  |  | $ 0 |  |  |  | $ 0 |  |  |  |  |  |  | $ 17,701 | [1] |  | $ 23,014 | $ 23,148 | [2] |  | $ 19,478 |  | $ 8,285 |  | $ 9,239 |  |  |  | $ 694 |  |  |  | $ 0 |  |  |  | $ 0 |  |  |  | $ 0 |  |  |  |  |  |  | $ 0 | [1] |  | $ 0 |  | $ 694 | [2] |  | $ 0 |  | $ 0 |  | $ 0
Defined Benefit Plan Fair Value Of Plan Assets Obligations For Collateral Received |  |  |  |  |  |  | 25,694 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 25,694 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Fair Value of Plan Assets |  |  | 68,085 | 70,610 | 66,984 | 278,000 | 277,598 | 255,327 | 1,895 | 1,327 | 19,790 |  | 2,098 | 2,791 | 99,315 |  | 262 | 353 | 35,353 |  | 63,830 | [3] | 66,139 | [4] | 58,755 | [5] |  |  | 23,868 |  |  |  | 22,987 |  | 9,290 |  | 8,642 |  | 2,419 | 3,197 | 180,138 | 167,340 | 59 | 53 | 2,256 |  | 2,098 | 2,791 | 99,315 |  | 262 | 353 | 35,353 |  | 0 | [3] | 0 | [4] | 43,214 | [5] |  |  | 0 |  |  |  | 0 |  | 0 |  | 0 |  | 65,666 | 67,413 | 97,573 | 109,564 | 1,836 | 1,274 | 17,534 |  | 0 | 0 | 0 |  | 0 | 0 | 0 |  | 63,830 | [3] | 66,139 | [4] | 15,541 | [5] |  |  | 23,579 |  |  |  | 22,987 |  | 9,290 |  | 8,642 |  | 0 | 0 | 289 | 694 | 0 | 0 | 0 |  | 0 | 0 | 0 |  | 0 | 0 | 0 |  | 0 | [3] | 0 | [4] | 0 | [5] |  |  | 289 |  |  |  |  | 0 |  | 0 |  | 0 |
Percentage investment in common stock of small-cap companies | 34.00% | 33.00% |  |  |  |  | 6.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage investment in common stock of mid-cap companies | 33.00% | 35.00% |  |  |  | 26.00% | 28.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage investment in common stock of large-cap companies | 32.00% | 31.00% | 49.00% | 53.00% |  | 26.00% | 24.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage investment in US Treasuries |  |  | 15.00% |  |  | 13.00% | 13.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage investment in mortgage backed securities |  |  | 12.00% | 12.00% |  |  | 11.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage investment in corporate bonds |  |  | 11.00% | 21.00% |  | 6.00% | 10.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage investment in foreign fixed-income investments |  |  |  |  |  |  | 8.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage investment in other investments |  |  | 13.00% | 14.00% |  | 29.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in net plan assets: [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value, Beginning Balance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 694 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  | 694 | 937 |  |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (261) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (2) |  | (259) | 189 |  |  |  |  |  |  |
Defined Benefit Plan, Purchases, Sales, and Settlements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | (144) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 291 |  | (435) | (432) |  |  |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value, Ending Balance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 289 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 289 |  | $ 0 | $ 694 |  |  |  |  |  |  |
[1] | (a) Collective and mutual funds invest approximately 28 percent in common stock of mid-cap U.S. companies, 24 percent in common stock of large-cap U.S. companies, 13 percent in U.S. Treasuries, 11 percent in mortgage-backed securities, 10 percent in corporate bonds, 8 percent in foreign fixed-income investments and 6 percent in common stock of small-cap U.S. companies.
[2] | (b) This class includes collateral held at December 31, 2010, as a result of participation in a securities lending program. Cash collateral is invested by the trustee primarily in repurchase agreements, mutual funds and commercial paper.
[3] | The insurance investment contract invests approximately 49 percent in common stock of large-cap U.S. companies, 15 percent in U.S. Treasuries, 12 percent in mortgage-backed securities, 11 percent in corporate bonds, and 13 percent in other investments.
[4] | The insurance investment contract invests approximately 53 percent in common stock of large-cap U.S. companies, 21 percent in corporate bonds, 12 percent in mortgage-backed securities and 14 percent in other investments.
[5] | a) Collective and mutual funds invest approximately 26 percent in common stock of mid-cap U.S. companies, 26 percent in common stock of large-cap U.S. companies, 13 percent in U.S. Treasuries, 6 percent in corporate bonds and 29 percent in other investments.

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