Merger details:

The Justice Department approved Sirius Satellite Radio’s $5 billion buyout of rival XM Satellite Radio on Monday, saying the deal was unlikely to hurt competition or consumers.

The deal was approved despite opposition from consumer groups and an intense lobbying campaign by the land-based radio industry.

The buyout received shareholder approval in November. The companies said the merger will save hundreds of millions of dollars in operating costs—savings that will ultimately benefit their customers.