Erika Riker -- the wife of former "American Idol" judge Randy Jackson -- has filed for divorce from Jackson after 18 years of marriage, TMZ reports.

According to TMZ, Riker is citing "irreconcilable differences" as the reason for divorce and is requesting full physical custody and joint legal custody of the couple's 17-year-old son, Jordan.

Riker and Jackson also have an adult daughter, Zoe, who is 19, and Jackson has a daughter Taylor from his previous marriage to Elizabeth Jackson.

In addition to requesting full custody, Riker is also requesting that Jackson be responsible to pay her legal fees, TMZ reports.

Although neither Jackson nor Riker have spoken publicly about the pending divorce, an insider for PEOPLE recently revealed that Jackson is "bummed out" about the marital split.

"Randy and Erika had a plan [of how they would file] but at the end of the day she decided to file [on Friday]," said the PEOPLE insider. "Randy is bummed out. It's not the way he wanted it to happen or end."

Riker and Jackson married in 1995 and since then have gone on to run the Randy and Erika Family Foundation, which focuses on dance and physical activity, the Los Angeles Sentinel reports.

In addition to running his foundation with his wife, Jackson also appeared as a judge for 12 seasons of "American Idol." Us Weekly reports.

Although Jackson is no longer a judge on the FOX singing competition, the 58-year-old producer still appears on "AI" as a mentor -- a decision he made back in 2013, according to Us Weekly.

Despite the claims that Jackson is "bummed out" about his divorce, he recently shared some positive advice with Us Weekly at the 8th Annual Clinton Global Citizen Awards in NYC.

"Be passionate about everything you do," he said. "And really learn in life to want what you need. I think we all want a lot of things, but it always comes down to what do we actually need? I'm trying to get better in wanting what I need. Because the need will help me get through the want just as another fulfillment."