Arnold Schwarzenegger and Maria Shriver are finally saying, "Hasta la vista, baby," to their 28-year marriage.

The long married couple's highly publicized divorce is in its final stages and should be settled by Christmas. Three and a half years after separating, the duo is said to be splitting amicably after agreeing to divide their massive $400 million fortune.

According to California law, Shriver, who is believed to be worth $100 million, is entitled to half of Schwarzenegger's $300 million earnings from their 25-year marriage. The longtime duo split after Schwarzenegger's shocking affair with the family's housekeeper Mildred Baena hit the media.

A source told MailOnline "It's been a long road, for a long time it wasn't a priority for either of them, but the divorce is almost complete. The lawyers are just ironing out the final details. … If everything goes to plan it should be tied up by Christmas."

The source went on to say, "When you have large fortunes to divide and legacies for the children to agree on, things aren't always as clearly defined as you'd imagine … But Maria and Arnold have resolved their differences and are on speaking terms, they have four kids together after all."

Both couples have moved on ... Schwarzenegger has a new lady love -- physical therapist Heather Milligan. And Shriver is now dating ABC news political analyst Matthew Dowd, whom she debuted at a Robert Kennedy's wedding a few weeks ago in Cape Cod, Massachusetts.

Good for them!