2.2.0.25falsefalse0202 - Disclosure - Basis of Preparationtruefalsefalse1falsefalseUSDfalsefalse1/1/2011 - 3/31/2011 USD ($) USD ($) / shares $Jan-01-2011_Mar-31-2011http://www.sec.gov/CIK0001267395duration2011-01-01T00:00:002011-03-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDEPSDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2true0ahl_BasisOfPreparationAndSignificantAccountingPoliciesAbstractahlfalsenadurationBasis of Preparationfalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringBasis of PreparationfalsefalseBasis of Preparation [Abstract]3false0us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlockus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00  <div align="left" style="margin-left: 0%"> <div style="margin-top: 12pt; font-size: 1pt">  </div> <table width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 11pt; font-family: Arial, Helvetica; color: #000000; background: transparent; text-align: left"> <tr> <td width="3%"></td> <td width="97%"></td> </tr> <tr valign="top"> <td> <b><font style="font-family: 'Times New Roman', Times">2.  </font></b> </td> <td> <b><font style="font-family: 'Times New Roman', Times">Basis of Preparation</font></b> </td> </tr> </table> <div style="margin-top: 6pt; font-size: 1pt">  </div> <div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 4%; font-size: 11pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"> The accompanying unaudited condensed consolidated financial statements have been prepared on the basis of generally accepted accounting principles in the United States (“GAAP”) for interim financial information and in accordance with the instructions to <font style="white-space: nowrap">Form 10-Q</font> and Article 10 of <font style="white-space: nowrap">Regulation S-X.</font> Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. Results for the three months ended March 31, 2011 are not necessarily indicative of the results that may be expected for the year ended December 31, 2011. The unaudited condensed consolidated financial statements include the accounts of Aspen Holdings and its wholly-owned subsidiaries, which are collectively referred to herein as the “Company.” All intercompany transactions and balances have been eliminated on consolidation. </div> <div style="margin-top: 6pt; font-size: 1pt">  </div> <div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 4%; font-size: 11pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"> The balance sheet at December 31, 2010 has been derived from the audited consolidated financial statements at that date but does not include all of the information and footnotes required by GAAP for complete financial statements. These unaudited condensed consolidated financial statements and notes thereto should be read in conjunction with the consolidated financial statements and notes thereto for the year ended December 31, 2010 contained in Aspen’s Annual Report on <font style="white-space: nowrap">Form 10-K</font> filed with the United States Securities and Exchange Commission (File <font style="white-space: nowrap">No. 001-31909).</font> </div> <div style="margin-top: 6pt; font-size: 1pt">  </div> <div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 4%; font-size: 11pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"> Assumptions and estimates made by management have a significant effect on the amounts reported within the consolidated financial statements. The most significant of these relate to losses and loss adjustment expenses, the value of investments, reinsurance recoverables and the fair value of derivatives. All material assumptions and estimates are regularly reviewed and adjustments made as necessary, but actual results could be significantly different from those expected when the assumptions or estimates were made. </div> <div style="margin-top: 12pt; font-size: 1pt">  </div> <div align="left" style="margin-left: 2%; margin-right: 0%; font-size: 11pt; font-family: Arial, Helvetica; color: #000000; background: transparent"> <b><font style="font-family: 'Times New Roman', Times">New Accounting Policies</font></b> </div> <div style="margin-top: 6pt; font-size: 1pt">  </div> <div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 4%; font-size: 11pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"> In December 2010, the FASB issued ASU <font style="white-space: nowrap">2010-28,</font> “<i>When to Perform Step 2 of the Goodwill Impairment Test for Reporting Units with Zero or Negative Carrying Amounts</i>.” Step 1 requires reporting entities to identify any potential impairments, on either an annual or interim basis, by comparing the estimated fair value of a reporting unit to its carrying value. If the estimated fair value is less than the carrying value and, it is more likely than not that an impairment exists, then the amount of the impairment will be assessed in the updated guidance in Step 2. Evaluating an impairment in Step 2 requires the evaluation of qualitative factors including the factors presented in existing guidance that trigger an interim impairment test of goodwill such as an adverse change in the business climate, unanticipated competition, or the expectation that a reporting unit will be sold or disposed. ASU <font style="white-space: nowrap">2010-28</font> is effective for annual reporting periods beginning after December 15, 2010. The provisions of the new guidance do not have a material impact on the Company’s consolidated financial statements. </div>  </div>   <div style="margin-left: 0%">  <div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 0%; font-size: 11pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"> </div>  <div style="margin-top: 0pt; font-size: 1pt">  </div> <div align="left" style="margin-top: 12pt; margin-left: 2%; margin-right: 0%; font-size: 11pt; font-family: Arial, Helvetica; color: #000000; background: transparent"> <b><font style="font-family: 'Times New Roman', Times">Accounting Pronouncements Not Yet Adopted</font></b> </div> <div style="margin-top: 6pt; font-size: 1pt">  </div> <div align="left" style="margin-left: 0%; margin-right: 0%; text-indent: 4%; font-size: 11pt; font-family: 'Times New Roman', Times; color: #000000; background: transparent"> In 2010, the FASB’s Emerging Issues Task Force issued ASU <font style="white-space: nowrap">2010-26,</font> “<i>Accounting for Costs Associated with Acquiring or Renewing Insurance Contracts</i>,” which requires costs to be incrementally or directly related to the successful acquisition of new or renewal insurance contracts to be capitalized as deferred acquisitions costs. This decision would require us to write back the proportion of our general and administrative deferred acquisition costs which relate to quoted business which does not successfully convert into a policy. We have undertaken a review to quantify the impact of the change. The maximum impact would be if we were required to write back all of the deferred underwriting costs and would result in a $21.6 million increase in cumulative operating expenses with the change being spread across the current and prior years. ASU <font style="white-space: nowrap">2010-26</font> is effective for annual reporting periods beginning after December 15, 2011 and we will not be early adopting this standard. </div> </div>  <!-- Begin Block Tagged NotefalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRepresents disclosure of any changes in an accounting principle, including a change from one generally accepted accounting principle to another generally accepted accounting principle when there are two or more generally accepted accounting principles that apply or when the accounting principle formerly used is no longer generally accepted. Also disclose any change in the method of applying an accounting principle, or any change in an accounting principle required by a new pronouncement in the unusual instance that a new pronouncement does not include specific transition provisions.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 154 -Paragraph 2, 17, 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 28 -Paragraph 23, 24 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 01 -Paragraph b -Subparagraph 6 -Article 10 falsefalseBasis of Preparation12Basis of PreparationUnKnownUnKnownUnKnownUnKnownfalsetrue