Windows 7 - Word-2010 Taking 100% CPU even after I closed the document

Greetings.

I tried to search for "Word High CPU" and it separated the words, yielding 123 pages of results. So I apologize for failing to properly search for this issue. And I'm quite certain I'm not alone.

Problem: I opened Word to copy/past something from a web page, then printed it and closed the document w/o saving it. (I didn't need it for posterity.) A few minutes later Norton pops up a warning that WINWORD is using 100% of at least 1 CPU. Indeed, Task Manager and Process Explorer both show 4 instances of WinWord. Process ecplorer shows me that two instances are from a document I created 8 hours ago and two are from the more recent case I just described.

Yes, I can and will kill these processes but what's going on? How can I find out what's keeping these processes going long after I have closed them? It reminds me of my first jalopy car that would occasionally diesel a few minutes after I had shut the engine.

Is this a known bug in my OS, or office or just Word? Norton has scanned a few times for sign's of malware so I will not now assume I have a virus or trojan.

Thank you for any help on this.