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Accumulated Other Comprehensive Income (Loss) - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
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Statement Of Income And Comprehensive Income [Abstract] |  |  |
Net unrealized gain (loss) on available for sale securities | $ (5.4) | $ 2.4 | $ 3.3
Fair value of the interest rate swap | $ (0.2) | $ (0.7) |

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- Definition Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669686-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e681-108580 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669646-108580 + Details
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