republic services , inc . notes to consolidated financial statements 2014 ( continued ) the letters of credit use $ 909.4 million and $ 950.2 million as of december 31 , 2012 and 2011 , respectively , of availability under our credit facilities . surety bonds expire on various dates through 2026 . these financial instruments are issued in the normal course of business and are not debt . because we currently have no liability for this financial assurance , it is not reflected in our consolidated balance sheets . however , we have recorded capping , closure and post-closure obligations and self-insurance reserves as they are incurred . the underlying financial assurance obligations , in excess of those already reflected in our consolidated balance sheets , would be recorded if it is probable that we would be unable to fulfill our related obligations . we do not expect this to occur . our restricted cash and marketable securities deposits include , among other things , restricted cash and marketable securities held for capital expenditures under certain debt facilities , and restricted cash and marketable securities pledged to regulatory agencies and governmental entities as financial guarantees of our performance related to our final capping , closure and post-closure obligations at our landfills . the following table summarizes our restricted cash and marketable securities as of december 31: .
ar december 31 , 2012 what was the ratio of the surety bond to the reimbursement obligation under the surety bonds
we own a 19.9% ( 19.9 % ) interest in a company that , among other activities , issues financial surety bonds to secure capping , closure and post-closure obligations for companies operating in the solid waste industry . we account for this investment under the cost method of accounting . there have been no identified events or changes in circumstances that may have a significant adverse effect on the recoverability of the investment . this investee company and the parent company of the investee had written surety bonds for us relating primarily to our landfill operations for capping , closure and post-closure , of which $ 1152.1 million was outstanding as of december 31 , 2012 . our reimbursement obligations under these bonds are secured by an indemnity agreement with the investee and letters of credit totaling $ 23.4 million and $ 45.0 million as of december 31 , 2012 and 2011 . off-balance sheet arrangements we have no off-balance sheet debt or similar obligations , other than operating leases and the financial assurances discussed above , which are not classified as debt . we have no transactions or obligations with related parties that are not disclosed , consolidated into or reflected in our reported financial position or results of operations . we have not guaranteed any third-party debt . guarantees we enter into contracts in the normal course of business that include indemnification clauses . indemnifications relating to known liabilities are recorded in the consolidated financial statements based on our best estimate of required future payments . certain of these indemnifications relate to contingent events or occurrences , such as the imposition of additional taxes due to a change in the tax law or adverse interpretation of the tax law , and indemnifications made in divestiture agreements where we indemnify the buyer for liabilities that relate to our activities prior to the divestiture and that may become known in the future . we do not believe that these contingent obligations will have a material effect on our consolidated financial position , results of operations or cash flows. .