Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Stock-Based Compensation Expense

The Company’s associated compensation expense, which is included in the caption “General and administrative expenses” in the consolidated statements of comprehensive income, is reflected in the table below for the periods presented.

	Year ended December 31,
In thousands	2014		2013		2012
Non-cash equity compensation	$	54,353	$	39,890	$	29,057

Schedule of Stock Option Activity

The following table summarizes stock option activity under the 2000 Plan for the periods presented:

	Outstanding				Exercisable
	Number of options		Weighted average exercise price		Number of options	Weighted average exercise price
Outstanding at December 31, 2011	173,000		$	0.36	173,000	$	0.36
Exercised	(173,000	)	$	0.36
Outstanding at December 31, 2012	—		—		—	—

Restricted stock [Member]

Summary of Changes in Non-vested Shares of Restricted Stock

A summary of changes in non-vested restricted shares from December 31, 2011 to December 31, 2014 is presented below.

	Number of non-vested shares		Weighted average grant-date fair value
Non-vested restricted shares at December 31, 2011	2,396,688		$	24.33
Granted	1,832,056		36.73
Vested	(889,446	)	22.63
Forfeited	(80,374	)	29.53
Non-vested restricted shares at December 31, 2012	3,258,924		$	31.64
Granted	522,518		48.98
Vested	(929,618	)	23.65
Forfeited	(137,512	)	35.96
Non-vested restricted shares at December 31, 2013	2,714,312		$	37.50
Granted	1,424,764		61.11
Vested	(1,007,166	)	35.91
Forfeited	(453,146	)	44.90
Non-vested restricted shares at December 31, 2014	2,678,764		$	49.40