In This Chapter
Sorting out common causes of confusion
Providing hard-to-find and often-overlooked key information
Delving into important technical aspects
Much as we want to, we can't cover every conceivable aspect of XBRL in a book this size. In this chapter, we help you understand ten or so things that would clutter and complicate a basic explanation of XBRL, but are useful to know.
XBRL makes heavy use of XLink, the XML Linking language. (You can read the XLink specification at
www.w3.org/TR/xlink.) You can spend your entire professional career using XBRL and never have to understand anything about XLink. But XLink does provide useful features that may be helpful to you. The XLink specification and what exactly XLink provides can be challenging to grasp. For those who have never worked with XLink, particularly technical people who will need to understand it, an introduction to XLink can help you understand what XLink does and why it's important.
The hardest thing to understand about XLink is the physical components —lots of details go into making XLink's functionality work. We don't go into the details of how XLink physically works; you can get that from the XBRL and the XLink specifications. We do provide the highlights, however.
What XLink provides is actually quite simple: connections between resources. It also is a mechanism for defining resources that add information to an XBRL taxonomy or XBRL instance.