You can use S&P Capital IQ to research the capital debt structure of a public company. Search for the company by name in Capital IQ using the search engine in the top left corner of the screen.
After pulling up Capital IQ's record of the company, select Capital Structure Summary or Capital Structure Details from the menu on the left of the screen. Both subjects are listed under the Financials/Valuation subheading.
Capital Structure Summary provides a public company's total outstanding debt (debt and common equity), as well as a general summary of the debt, taken from the company's SEC filings:
Capital Structure Details breaks down the company's debt by specific debt instrument: