WASHINGTON (AP) - A bipartisan Senate immigration bill would put the 11 million immigrants in the country illegally on a 13-year path to U.S. citizenship that would cost $2,000 in fines plus additional fees, and would begin only once steps have been taken to secure the border, according to an outline of the measure released Monday.

The sweeping legislation also would remake the nation's inefficient legal immigration system, creating new immigration opportunities for tens of thousands of high- and low-skilled workers, as well as a new "merit visa" aimed at people with talents to bring to the U.S. as well as employment or family ties. Senators planned to formally introduce the bill today, but after the tragedy at the Boston Marathon a planned press event was delayed until later in the week.

Employers would face tough new requirements to check the legal status of all workers. The bill would institute a fundamental shift in an immigration system long focused on family ties, placing more importance on prospective immigrants' skills and employment potential.

Billions of dollars would be poured into border security, and millions of people who've been waiting overseas for years, sometimes decades, in legal immigration backlogs would see their cases speeded up.

Overall, the changes represent the most dramatic overhaul to U.S. immigration law in more than a quarter-century, and also would usher in major shifts to the U.S. employment landscape.

"I've always said that Americans will be commonsense, practical and balanced toward legal immigration and the 11 million who are here, provided that they are convinced that there won't be future flows of illegal immigration, and that has been the philosophy I think that's guided our group," said Sen. Chuck Schumer, D-N.Y. "We've put together a proposal that pretty much does that."

The bill is the result of months of secretive negotiations among eight lawmakers, equally divided between the two parties. In addition to Schumer and McCain, they are Democrats Dick Durbin of Illinois, Robert Menendez of New Jersey and Michael Bennet of Colorado, working with Republicans Marco Rubio of Florida, Lindsey Graham of South Carolina and Jeff Flake of Arizona.

Because of the makeup of the group, including conservatives and liberals, the legislation is a painstaking attempt to balance a focus on border security and legal enforcement sought by Republicans in the group, with Democratic priorities including making citizenship widely accessible.