Investors are normally content to simply let health insurers invest their capital wisely. Companies like UnitedHealth Group (NYSE:UNH) and WellPoint (NYSE:WLP) just have to give a quarterly update about how much is in the coffers and how much the company made from its investments to keep investors happy.

But these are extraordinary times. So Aetna (NYSE:AET) decided to open up the books and give investors a closer look at its balance sheet on Monday.

I have to say, the health insurer's capital structure is looking pretty healthy. Not every investment is at the same level as earlier in the year, but Aetna is far from being the next AIG (NYSE:AIG). Aetna is not so flush that it plans to up its token dividend, but the company doesn't expect to need an infusion of cash in the foreseeable future either. Call it a happy medium, which is a good place to be in this market.

Aetna and Humana (NYSE:HUM) did have Lehman Brothers and AIG bonds in their investment portfolios, but Aetna says that none of the companies in which it currently holds bonds are teetering on the brink of bankruptcy.

Aetna has also lost some money on mortgage-backed securities, but that's really only a paper loss, and the company is still receiving interest payments as expected. Most importantly, most are from before 2006 when property values were still appreciating, so major losses shouldn't be expected even if the value of the securities has gone down.

The company expects to see earnings growth of 3% to 5% next year. While that's nothing to get excited about, Aetna is basically priced like there won't be any growth in the foreseeable future. If the company can wiggle through 2009 and avoid any major interruptions in business, it should be in good shape when the economy picks up.

WellPoint and UnitedHealth Group are Motley Fool Inside Value recommendations. UnitedHealth Group is a Motley Fool Stock Advisor selection. The Fool owns shares of UnitedHealth Group. Try any of our Foolish newsletters today, free for 30 days

Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. The Fool's disclosure policy writes romance novels under a pseudonym.