Some writers struggle to fill the page and reach that 75,000 to 85,000-word mark. Others must cut words from draft after draft for fear of the presses quitting in protest before their books are produced. However, the amount of detail is not nearly as important as the quality of detail you put into your writing. As an example, I've included an excerpt from my unpublished novel "The Promethean Remnant" below:
Excerpt from "The Promethean Remnant" -
The palace's grandiose appearance, like a castle hidden away in a dark, remote ravine, convinced Celesta that she had at least one viable suspect in whatever crime, insult, or indiscretion she had been called in to investigate.
Grinning, Celesta confided in the nymph as they walked toward the palace, "Trust me on this...the butler did it."
The nymph, who was walking beside Celesta as they approached the sea-goddess's palace, looked at Celesta with something like confusion - or maybe it was boredom. The nymph's soft features could either be extremely expressive (as they had been back in the apartment, when the nymph was considering Henry) or her expression could be as still and blank as water on a windless day, making her nearly impossible to read.
"Butler?" the nymph inquired in a voice that sounded like a summer brook. "What is that?"
Did I need to include that much detail about both the palace and the nymph's expression? Probably not. Those details have nothing to do with the larger plot arc of this novel. However, by explaining that the palace looked like a castle, it allows Celesta to jump to the corny conclusion that 'the butler did it'.
Explaining how fluid and un-human the nymph's feature are reinforces the fact that, while the nymph knows the Greek pantheon well, she probably has never read Sir Arthur Conan Doyle. That simultaneously gives the reader something familiar (of course the butler did it!) and shows the reader and the main character that pop culture references will likely be useless for most of the pantheon and their courtiers.
In conclusion, there's nothing wrong with adding details to your writing, as long as they are the right details. Do your descriptions pull the reader into the world you are creating? Or do the details have your reader using your story as the best-known cure for insomnia?
Details and descriptions should deepen the experience of your story without lengthening to the point of boredom. It is a fine line, and one that you might not even notice until you allow someone else to read your writing. My recommendation is to write in as many details as you want...but be prepared to remove the excess to improve the overall quality of your writing.