I am conducting financial statement analysis on Apple and I noticed that the company has interest received that exceeds interest expense. In Apple's 2016 10-K form page 27 shows "Other Income/(Expense), Net" where Interest and Dividend Income of 3,999 exceeds the Interest Expense of 1,456 for the year 2016. When I look at the consolidated income statement on page 39, I find that these two figures are aggregated under "Other income/(expense), net".
I have previously only analysed companies that have an interest expense, which is included as a separate line item on the Income Statement, and I use this item in the calculation of ratios such as Interest Coverage Ratio.
My question is, should I separate the interest expense from interest received, and use the interest expense figure to calculate the Interest Coverage Ratio? Or should I not calculate this ratio in this case? I found an example online for Colgate where this ratio is not computed when interest expense was negative (see the Excel table in the link).
Also, does having a net interest received mean that the company has a negative cost of debt?