Since people will hit the i don't care he is a smart businessman button. Let's dive into the revelations a little deeper:
* Trump has basically no liquid assets. He has pretty much sold all his stock assets in order to pay off debt, and any time he got money from other sources (such as the apprentice) he used it as a down payment on loans to buy more property. Most of this property is underwater, taking out more and more debt to make payments. It would not surprise me if his net worth is close to being negative.
* He has been paying his family members "consulting fees" in the range of tens-hundreds of millions of dollars and writing those off as loses, which is pretty much the same thing his daddy did with him.
* Most of his newer businesses, i.e. the golf courses and new real estate projects since 2005 (when he went on a buying splurge with the apprentice money) have consistently lost money before depreciation (the excuse he uses) was even taken into account. His few actually profitable businesses were generally inherited from his father or are from Trump Tower (which is already paid for and as a large building in Manhatten makes good money on rents).
* There is a bunch of shady dealings with lobbyists using exorbitantly priced rooms/venues from his company for basically no reason. This is even more extensive than previously thought.
* His ass got saved by Obama's recession relief package. It allowed him to carry back loses further than two years, which netted him a much needed ~$70 million refund. In addition it allowed him to defer paying taxes on canceled loans from the recession (which are normally taxed as income) until 2014, which would have pushed his business under if he had to eat those taxes during the recession.
* The audit he is currently under is related to the above. To claim the refund from 2005-2007 he used him abadoning his stake in his Atlantic casinos to count as his loss. However in the tax code you can only do this if you receive nothing else from the business or bankruptcy, but he received a 5% stake in the restructured company after the bankruptcy, meaning all those refunds+interest would come due (~100 million dollars).
Small note on where the NYT is getting this from, it seems they got most of the tax information from someone high up in the Trump Organization, as they do not have Trump's full personal finances, just which business losses he was claiming for those finances. That being said, something like 95% of Trumps assets are in the Trump Organization, so this is a distinction without much of a difference. It really means all we are missing is an actual approximation of his net worth.
TL
R- The Trump Organization is a giant Rube-Goldberg machine juggling a bunch of flaming chainsaws, passing debt around and declaring losses while stuffing the few profits into tax havens to keep the business afloat, and virtually every business venture Trump has gotten into has failed and is underwater, and when that debt comes due he is screwed.