Annual report pursuant to Section 13 and 15(d)

Accumulated Other Comprehensive Income (Details Textual)

v2.4.1.9
Accumulated Other Comprehensive Income (Details Textual) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Realized gain $ 1.3us-gaap_AvailableForSaleSecuritiesGrossRealizedGains $ 10.8us-gaap_AvailableForSaleSecuritiesGrossRealizedGains  
Unrealized gain reclassified $ 0.9us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax $ 7.5us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax  
Effective tax rate 0.00%us-gaap_EffectiveIncomeTaxRateContinuingOperations (1.50%)us-gaap_EffectiveIncomeTaxRateContinuingOperations 24.80%us-gaap_EffectiveIncomeTaxRateContinuingOperations
Unrealized gain (loss) in Accumulated OCI      
Effective tax rate 40.13%us-gaap_EffectiveIncomeTaxRateContinuingOperations
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember
38.47%us-gaap_EffectiveIncomeTaxRateContinuingOperations
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember