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Retirement Plans (Weighted-Average Expense Assumptions) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended
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Mar. 31, 2014 | Mar. 31, 2013
Retirement Income Plan [Member] |  |
Defined Benefit Plans And Other Postretirement Benefit Plans [Line Items] |  |
Discount rate | 5.16% | 4.42%
Expected return on plan assets | 6.92% | 7.40%
Rate of compensation increase | 4.00% | 4.00%
Estimated contribution from the employer | $ 2.7 |
Retirement Life Plan [Member] |  |
Defined Benefit Plans And Other Postretirement Benefit Plans [Line Items] |  |
Discount rate | 4.85% | 4.42%
Expected return on plan assets | 0.00% | 0.00%
Rate of compensation increase | 0.00% | 0.00%
Scenario, Forecast [Member] | Retirement Income Plan [Member] |  |
Defined Benefit Plans And Other Postretirement Benefit Plans [Line Items] |  |
Estimated contribution from the employer | $ 9.8 |

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- Definition The interest rate used to adjust for the time value of money. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Expected Long-Term Rate of Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512013 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Expected rate of compensation increases (for pay-related plans). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(2) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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