NCO Group surged more than 40% Tuesday after the company's CEO offered to acquire all of the outstanding shares of the Horsham, Pa.-based outsourcing services company for $27.50 in cash each.

The executive, Michael J. Barrist, intends to partner in with One Equity Partners II and to finance the deal through a combination of $388 million of equity and about $815 million of debt.

The company's board is scheduled to meet later Tuesday to form a special committee of independent directors to consider the proposal. The special committee will retain independent financial advisors and legal counsel, the company said. Shares were up $7.26 to $26.31 in recent trading.

Camtek ( CAMT - Get Report) gained after the Israel-based automatic optical inspection systems company said first-quarter revenue increased 172% to $24.9 million. The company posted income of $4.4 million, or 16 cents a share, up from a loss of $2.4 million, or 9 cents a share, a year ago. Shares were up 83 cents, or 12.8%, to $7.33 in recent trading.

IDT ( IDT - Get Report) surged on news that Liberty Media ( LINTA) planned to buy IDT Entertainment from the Newark, N.J.-based telecommunications and entertainment company for $186 million in cash.

Under the deal, which is expected to close within the next three months, Liberty Media will pay IDT $186 million in cash and all of Liberty Media's equity interests in IDT and its subsidiaries, including about 17.2 million shares of IDT's Class B common stock and Liberty Media's roughly 5% interest in IDT Telecom. Liberty will also assume IDT Entertainment's existing debt.

On closing, IDT Entertainment and Liberty's Starz Entertainment Group will enter into a five-year programming output agreement for the broadcast of certain IDT programming on Starz's premium channels. Shares of IDT gained $1.81, or 16.2%, to $12.96 in recent trading. Liberty Media climbed 15 cents, or 0.8%, to $18.30.

Zumiez ( ZUMZ - Get Report) fell after the Everett, Wash.-based adventure-sports gear and accessories retailer was downgraded by Piper Jaffray to market perform from outperform. Shares slipped $2.48, or 7.2%, to $32.05 in recent trading.

Greenbrier ( GBX - Get Report) stumbled on Monday's news that the railcar maker will take a $2.9 million after-tax charge in its consolidated statement of operations in the third quarter ending May 31, following a tentative settlement with the Internal Revenue Service.

The IRS had audited the company's federal income tax returns for the years ended 1999 to 2002 and reviewed the company's decision to take a tax deduction for $52.6 million on its 2002 federal tax return relating to European operations. The agreement is subject to the final approval of the IRS.

Separately, the Lake Oswego, Ore., company plans to issue $85 million convertible senior notes due 2026 in a private offering. Greenbrier said it also intends to grant the initial purchasers of the notes an option to purchase up to an additional $15 million aggregate principal amount of notes. The company anticipates that the closing of the offering will take place on or about May 22. Shares fell $2.38, or 6.1%, to $36.98 in recent trading.