Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

This Christmas spirit was in full swing on Wall Street today with a double-dose of poor economic data hitting the tape and the broad-based S&P 500 (^GSPC 1.20%) shrugging it off and hitting another fresh all-time high anyway.

First, the weekly report from the Mortgage Brokers Association showed that weekly loan originations dropped 6.3% from the previous week. This figure is very sensitive to interest rates, and rates recently bounced a bit, so it's not a huge surprise. I would point out, though, that U.S. consumers have been spoiled with low interest rates for years, and their insistence on waiting for even lower rates may turn out to be a poor decision for them and the homebuilding sector.

Along those same lines, new home sales for November fell 10,000 to a seasonally adjusted annual rate of 464,000. The 2.1% month-over-month drop was actually a bit less than economists expected, but it nonetheless points to an ongoing weakening in the housing market.

By day's end, the S&P 500 jumped higher by another 5.33 points (0.29%) to close at 1,833.32. The index is now up approximately 27% year to date.

Leading all stocks higher today, despite a lack of market-specific news, was hepatitis-C-focused therapy developer Idenix Pharmaceuticals (NASDAQ: IDIX), which jumped by 18.2% on this shortened day of trading. Despite its recent pipeline woes and the ongoing clinical hold of IDX20963, which is anticipated to be a game-changing experimental compound for Idenix, the potential for royalty compensation derived from a patent dispute with Gilead Sciences over the recently approved hepatitis-C medication, Sovaldi, could be today's upside culprit. As for me, I prefer to the let the pipelines, not the courtrooms, do the talking, and Idenix has been practically put on mute by its competitors up until now.

Sticking within the biotech sector, Supernus Pharmaceuticals (SUPN 0.81%) added 13.2% as a continuation of a move from yesterday's approval by the Food and Drug Administration of Orenitram for the treatment of pulmonary arterial hypertension. The drug, which will benefit United Therapeutics (UTHR 0.17%) the most, as we saw from yesterday's 30% romp higher, also allows Supernus to collect milestone and single-digit royalties on worldwide sales of the drug. Specifically, Supernus could be entitled to a $2 million royalty payment for the FDA approval of the drug. While this is good news, I might hold my cheering until we see how well Orenitram sells.

Finally, shares of thermal coal miner Westmoreland Coal (WLB) shot higher by 11.2% after announcing the acquisition of Sherritt International's Prairie and Mountain coal mining operations for $435 million. The deal includes seven thermal coal mines and a 50% interest in an activated carbon plant and char production facility in Canada. In addition, the deal is expected to immediately be cash flow-positive for Westmoreland Coal. While I certainly appreciate Westmoreland's aggressiveness, I'm still a bit concerned about the possibility for integration issues as well as the ongoing weakness in thermal coal pricing. I'd rather take a back seat here for the time being and see how this situation plays out.