Debt	3 Months Ended
Mar. 31, 2013
Debt Disclosure [Abstract]
Debt	DEBT In December 2011, United Fire entered into a credit agreement with a syndicate of financial institutions as lenders, KeyBank National Association as administrative agent, lead arranger, sole book runner, swingline lender, and letter of credit issuer, and Bankers Trust Company as syndication agent. The four-year credit agreement provides for a $100,000 unsecured revolving credit facility that includes a $20,000 letter of credit subfacility and a swing line subfacility of up to $5,000. During the term of this credit agreement, we have the right to increase the total credit facility from $100,000 up to $125,000 if no event of default has occurred and is continuing and certain other conditions are satisfied. The credit facility is available for general corporate purposes, including working capital, acquisitions and liquidity purposes. Principal of the credit facility is due in full at maturity, on December 22, 2015. The interest rate is based on our monthly choice of either a base rate or the London Interbank Offered Rate (“LIBOR”) plus, in each case, a calculated margin amount. A commitment fee on each lender's unused commitment under the credit facility is also payable quarterly. The credit agreement contains customary representations, covenants and events of default, including certain covenants that limit or restrict our ability to engage in certain activities. Subject to certain exceptions, these activities include restricting our ability to sell or transfer assets or enter into a merger or consolidate with another company, grant certain types of security interests, incur certain types of liens, impose restrictions on subsidiary dividends, enter into leaseback transactions, or incur certain indebtedness. The credit agreement contains certain financial covenants including covenants that require us to maintain a minimum consolidated net worth, a debt to capitalization ratio and minimum stockholders' equity. There was no outstanding balance on the credit facility at March 31, 2013. The outstanding balance on the line of credit was $45,000 at March 31, 2012 at an interest rate of 2.0 percent. For the three-month period ended March 31, 2013, we did not incur any interest expense related to this credit facility. For the three-month period ended March 31, 2012, we incurred $341 in interest expense related to this credit facility. We were in compliance with all covenants for the credit agreement at March 31, 2013. In connection with our acquisition of Mercer Insurance Group, we acquired three statutory trusts with outstanding issuances of trust preferred securities with a balance as of the acquisition date of $15,614. We redeemed two of the issuances totaling $8,035 during the three-month period ended March 31, 2012 and the remaining issuance in full in April 2012. We incurred $151 of interest expense related to these trust preferred securities for the three-month period ended March 31, 2012.

DEBT

In December 2011, United Fire entered into a credit agreement with a syndicate of financial institutions as lenders, KeyBank National Association as administrative agent, lead arranger, sole book runner, swingline lender, and letter of credit issuer, and Bankers Trust Company as syndication agent. The four-year credit agreement provides for a $100,000 unsecured revolving credit facility that includes a $20,000 letter of credit subfacility and a swing line subfacility of up to $5,000.

During the term of this credit agreement, we have the right to increase the total credit facility from $100,000 up to $125,000 if no event of default has occurred and is continuing and certain other conditions are satisfied. The credit facility is available for general corporate purposes, including working capital, acquisitions and liquidity purposes. Principal of the credit facility is due in full at maturity, on December 22, 2015. The interest rate is based on our monthly choice of either a base rate or the London Interbank Offered Rate (“LIBOR”) plus, in each case, a calculated margin amount. A commitment fee on each lender's unused commitment under the credit facility is also payable quarterly.

The credit agreement contains customary representations, covenants and events of default, including certain covenants that limit or restrict our ability to engage in certain activities. Subject to certain exceptions, these activities include restricting our ability to sell or transfer assets or enter into a merger or consolidate with another company, grant certain types of security interests, incur certain types of liens, impose restrictions on subsidiary dividends, enter into leaseback transactions, or incur certain indebtedness. The credit agreement contains certain financial covenants including covenants that require us to maintain a minimum consolidated net worth, a debt to capitalization ratio and minimum stockholders' equity.

There was no outstanding balance on the credit facility at March 31, 2013. The outstanding balance on the line of credit was $45,000 at March 31, 2012 at an interest rate of 2.0 percent. For the three-month period ended March 31, 2013, we did not incur any interest expense related to this credit facility. For the three-month period ended March 31, 2012, we incurred $341 in interest expense related to this credit facility. We were in compliance with all covenants for the credit agreement at March 31, 2013.

In connection with our acquisition of Mercer Insurance Group, we acquired three statutory trusts with outstanding issuances of trust preferred securities with a balance as of the acquisition date of $15,614. We redeemed two of the issuances totaling $8,035 during the three-month period ended March 31, 2012 and the remaining issuance in full in April 2012. We incurred $151 of interest expense related to these trust preferred securities for the three-month period ended March 31, 2012.