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Subsequent Event (Narrative) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended
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Mar. 31, 2013
Subsequent Events |
Preliminary purchase price for NAC | $ 42.4
Contract gross price for NAC | 45.0
Working capital adjustment for NAC | 2.6
Preliminary cash proceeds for sale of NAC | 39.9
Estimated gain on sale of NAC, minimum | 30.0
Estimated gain on sale of NAC, maximum | $ 40.0

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- Definition This item represents the amount of net sales proceeds received on disposal of an equity method investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 35 -URI http://asc.fasb.org/extlink&oid=7658923&loc=d3e32847-111569 + Details
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- Details
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