"We hope these comments and the appended information will be helpful as further consideration is given to more suitable standards for insurance enterprises with thrifts and banking entities," the letter says.

It adds that the NAIC's "technical experts stand ready to answer additional questions in person or by telephone."

The letter was signed by Therese Vaughn, the NAIC's retiring CEO, and Kevin McCarty, Florida insurance commissioner and current NAIC president.

"We are confident once a better understanding of the existing financial standards required of such insurers is reached, more progress can be made toward developing a regulatory approach that captures the complete risk profile of an insurance enterprise," the letter says.

Provisions of the Dodd-Frank financial services reform law mandate that the Federal Reserve Board and the Office of the Comptroller of the Currency assume oversight of savings and loans that were formerly the responsibility of the Office of Thrift Supervision (OTS), which has been phased out.

Under the law, the Fed is replacing the OTS as the consolidated regulator of thrift holding companies formerly overseen by the OTS.

The 62-page NAIC comment letter includes an appendix that lists the outstanding surplus notes of all property and casualty, life, fraternal, title and health insurance companies chartered by the states.

It even talks about the financial health of eight insolvent insurance companies.

These include PMI Mortgage Insurance Co., based in Arizona, which has negative capital of more than $2 billion. Three health companies are listed as insolvent, one in Florida, one in New York and another in Guam. A risk-retention group formed by the scaffold industry in Washington, D.C. is also listed as insolvent, but only to the tune of $190,000.