v2.4.0.8

Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2013 | Dec. 31, 2011 | Dec. 31, 2012 | Dec. 31, 2010
Income Taxes [Line Items] |  |  |  |
Reduction in net deferred tax assets | $ 22.7 | $ 233.7 |  |
Amortization period for tax basis intangibles, years | 15 years |  |  |
Taxable loss of partnership |  | 56.8 |  | 81.4
Taxable loss carried back and utilized against prior year taxable income | 8.8 |  |  |
Taxable loss, utilized against taxable income | 54.6 |  | 74.9 |
Carryforward period for tax basis intangibles, years | 20 years |  |  |
Unrecognized tax benefits that if recognized would affect the annual effective rate | 18.9 |  | 26.8 |
Interest expense accrued | 1.0 | 1.5 | 5.8 |
Accrued Penalties | $ 0 | $ 0 | $ 0.5 |

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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 + Details
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- Definition Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
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