Thrivent Financial for Lutherans announced Thursday that it will soon extend eligibility for its membership, which was previously reserved for Lutherans, to all Christians.

Minneapolis-based Thrivent is a Fortune 500 company and Minnesota’s second-largest private company based on revenue, which totaled $8.3 billion in 2012. It provides advising and banking, investment, and insurance services.

Thrivent describes its change as an extension of its “common bond” to all Christians. As a tax-exempt fraternal benefit society, the organization said it is legally required to serve members who share a common bond—in this case, religion.

The move will significantly broaden the company's potential client base. Most customers are considered members, and as of the end of last year, Thrivent had 2.5 million members.

A vote was held in March and April, and 72 percent of voting members favored the change. About 425,000 members participated in the vote, representing 21 percent of Thrivent’s total membership. The vote drew the attention of many: The organization said typical votes only attract 10 percent of members. Thrivent’s board voted unanimously in May to approve the change.

“One of the unique aspects of Thrivent is that our benefit members are our owners, so they get to make these important decisions,” Thrivent President and CEO Brad Hewitt said in a statement. “This vote will allow us to strengthen our mission of helping more Christians be wise with money and live generously.”

The organization will continue to use the shortened form of its name, Thrivent, in certain marketing materials, although it will retain its legal name, Thrivent Financial for Lutherans, spokesman Brett Weinberg told Twin Cities Business.

The phasing in of Thrivent’s new membership eligibility will be a “very gradual progress” with changes likely to occur at the beginning of next year, he said.

With respect to how it defines “Christian,” Thrivent said that “Christian faith is described in the Apostles' Creed, which Lutherans and a majority of Christians have used for hundreds of years to profess their faith. Christians who share these beliefs will be invited to join our organization.”

Last fall, Thrivent announced plans to turn its bank into a credit union.