Acadia Healthcare executives have increased the size of their secondary offering of shares by more than a fifth and now could raise more than $180 million to help fund their planned acquisition of peers with operations in Arkansas, Michigan, Ohio and Texas.

Original plans called for Franklin-based Acadia to sell 6 million shares and have a so-called greenshoe of another 900,000 shares. Investor interest has since grown those numbers to 7 million and 1.05 million, respectively. That has lifted the potential total take for Acadia boss Joey Jacobs and his team to about $180 million from $150 million. (Large investor Waud Capital, as well as a number of Acadia officials, also are selling some of their shares in the offering.)

Acadia will sell its shares at $22.50 each, a discount of just 1.5 percent to their Thursday closing price. So far this year, the stock (Ticker: ACHC) has risen more than 120 percent, giving Acadia a market cap of almost $1 billion.