Stockholders' Equity

12 Months Ended

Dec. 31, 2013

Stockholders' Equity Note [Abstract]

Stockholders' Equity

Stockholders' Equity

Shares of our common stock outstanding and activity for the years ended December 31, 2013, 2012 and 2011 are presented below:

	Years Ended December 31,
	2013		2012		2011
	(In thousands)
Common shares outstanding at January 1	203,551,496		209,332,646		106,529,376
Common shares issued in connection with merger with Frontier	—		—		103,270,002
Issuance of restricted stock, excluding restricted stock with performance feature	292,855		691,207		512,880
Vesting of performance units	210,819		869,231		233,134
Vesting of restricted stock with performance feature	15,141		146,400		124,332
Forfeitures of restricted stock	(15,794	)	(3,975	)	(3,730	)
Purchase of treasury stock (1)	(5,224,166	)	(7,484,013	)	(1,333,348	)
Common shares outstanding at December 31	198,830,351		203,551,496		209,332,646

(1) Includes 235,922, 560,484 and 747,225 shares, respectively, withheld under the terms of stock-based compensation agreements to provide funds for the payment of payroll and income taxes due at the vesting of share-based awards, as well as other stock repurchases under separate authority from our Board of Directors.

We have a Board approved repurchase program that authorizes us to repurchase common stock in the open market or through privately negotiated transactions. The timing and amount of stock repurchases will depend on market conditions, corporate, regulatory and other relevant considerations. This program may be discontinued at any time by the Board of Directors. As of December 31, 2013, we had remaining authorization to repurchase up to $311.6 million under this stock repurchase program.

In May 2012, we entered into a structured share repurchase arrangement with a financial institution under which we provided an up-front cash payment of $100.0 million and, depending on market conditions, would either receive shares of our common stock or cash at the expiration of the agreement. The agreement expired in September 2012 at which time we received our up-front payment plus an additional $8.6 million in cash that was recorded as additional capital.

During the years ended December 31, 2013, 2012 and 2011, we withheld shares of our common stock from certain employees in the amounts of $11.3 million, $22.4 million and $24.9 million, respectively. These withholdings were made under the terms of restricted stock and performance share unit agreements upon vesting, at which time, we concurrently made cash payments to fund payroll and income taxes on behalf of officers and employees who elected to have shares withheld from vested amounts to pay such taxes.