Stock-Based Compensation, Restricted Stock Awards and Stock Options (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012		Jun. 30, 2012
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock unit awards approved (in shares)	783,333
Number of restricted stock units for which performance targets established (in shares)			220,000
Unrecognized compensation cost related to the unvested awards	$ 8,400,000		$ 8,400,000
Weighted average period over which unrecognized compensation cost is expected to be recognized (in years)			2 years 9 months 18 days
Number of shares of common stock exchanged for each award (in shares)			1
Aggregate number of shares approved (in shares)	4,875,833		4,875,833
Number of Shares, Restricted Stock Unit Awards [Abstract]
Granted and unvested, beginning of period (in shares)			1,185,832
Vested (in shares)			(208,332)
Granted (in shares)			293,333
Forfeited (in shares)			(120,833)
Total Granted and Unvested (in shares)	1,150,000		1,150,000
Approved for grant (in shares)	888,335		888,335
Total Awarded and Unvested, end of period (in shares)	2,038,335		2,038,335
Weighted Average Grant Date Fair Value, Restricted Stock Unit Awards [Abstract]
Granted and Unvested, beginning of period (in dollars per share)			$ 19.65
Vested (in dollars per share)			$ 24.36
Granted (in dollars per share)			$ 14.72
Forfeited (in dollars per share)			$ 13.47
Total Granted and Unvested, end of period (in dollars per share)	$ 18.19		$ 18.19
Approved for grant (in dollars per share)	$ 0	[1]	$ 0	[1]
Aggregate Intrinsic Value, Restricted Stock Unit Awards [Abstract]
Granted and Unvested, beginning of period			14,633,167
Vested			2,626,729
Granted			3,716,529
Forfeited			0
Total Granted and Unvested	14,570,500		14,570,500
Approved for grant	11,255,204		11,255,204
Total Awarded and Unvested, end of period	25,825,704		25,825,704
Outstanding unvested awards [Abstract]
2012 (in shares)	0		0
2013 (in shares)	905,000		905,000
2014 (in shares)	408,335		408,335
2015 (in shares)	150,000		150,000
2016 (in shares)	165,000		165,000
2017 (in shares)	410,000		410,000
Total (in shares)	2,038,335		2,038,335
Number of unvested stock awards that will vest subject to the satisfaction of service-based requirements (in shares)			245,000
Number of unvested stock awards that will vest subject to the satisfaction of service-based requirements and the achievement of performance metrics (in shares)			1,793,335
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock option awards for which pre-tax income performance targets established (in shares)			150,000
Number of installments for vesting of stock awards			5
Unrecognized compensation cost related to the unvested awards	2,900,000		2,900,000
Weighted average period over which unrecognized compensation cost is expected to be recognized (in years)			2 years 9 months 18 days
Award of new stock options			695,000
Outstanding unvested awards [Abstract]
Term of Stock Options			10 years
Aggregate number of stock option awards approved for grant (in shares)			2,380,465
Number Of Shares, Stock Options [Abstract]
Total Awarded and Outstanding, beginning of period (in shares)			1,225,465
Granted (in shares)			165,000
Forfeited (in shares)			(75,000)
Total Granted and Outstanding (in shares)	1,315,465		1,315,465
Approved for grant (in shares)	830,000		830,000
Total Awarded and Unvested, end of period (in shares)	2,145,465		2,145,465
Weighted Average Grant Date Fair Value, Stock Options [Abstract]
Total Awarded and Outstanding, beginning of period (in dollars per share)			$ 10.11
Granted (in dollars per share)			$ 5.65
Forfeited (in dollars per share)			$ 7.20
Total Granted and Outstanding, end of period (in dollars per share)	$ 9.72		$ 9.72
Approved for grant (in dollars per share)	$ 0	[1]	$ 0	[1]
Weighted Average Exercise Price, Stock Options [Abstract]
Total Awarded and Outstanding, beginning of period (in dollars per share)			$ 18.45
Granted (in dollars per share)			$ 19.51
Forfeited (in dollars per share)			$ 0
Total Granted and Outstanding (in dollars per share)	$ 18.91		$ 18.91
Approved for grant (in dollars per share)	$ 12.80		$ 12.80
Total Awarded and Outstanding, end of period (in dollars per share)	$ 16.55		$ 16.55
Number of vested and exercisable options (in shares)	490,465		490,465
Vested and exercisable options, weighted average exercise price (in dollars per share)	$ 19.79		$ 19.79
Number of unvested stock option awards that will vest subject to the satisfaction of service-based requirements	592,500		592,500
Number of unvested stock option awards that will vest subject to the satisfaction of service-based requirements and the achievement of performance metrics (in shares)	1,062,500		1,062,500
Intrinsic value of outstanding options	$ 100,000		$ 100,000
Weighted average remaining contractual term of outstanding options (in years)			7 years 1 month 6 days
Number of options for which fair value assumptions used (in shares)			750,000
Stock Options - Fourth Tranche [Member]
Weighted Average Exercise Price, Stock Options [Abstract]
Number of options for which fair value assumptions used (in shares)			150,000
Fair value assumptions using the Black-Scholes option pricing model [Abstract]
Risk free interest rate (in hundredths)			0.88%
Expected life of options (in years)			4 years 4 months 24 days
Expected volatility of underlying stock (in hundredths)			53.89%
Expected quarterly dividends ( (in dollars per share)			$ 0.00
Stock Options - Service Based Vesting Options [Member]
Weighted Average Exercise Price, Stock Options [Abstract]
Number of options for which fair value assumptions used (in shares)			15,000
Fair value assumptions using the Black-Scholes option pricing model [Abstract]
Risk free interest rate (in hundredths)			1.12%
Expected life of options (in years)			7 years 3 months 18 days
Expected volatility of underlying stock (in hundredths)			50.59%
Expected quarterly dividends ( (in dollars per share)			$ 0.00

[1] Grant date fair value cannot be determined currently because the related performance targets for future years have not yet been established by the Compensation Committee.