Share-Based Payments - Table 3 (Details) (Restricted Stock [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Nonvested shares, Beginning Balance, Shares	1,889
Nonvested shares, Beginning Balance, Weighted-Average Grant Date Fair Value	$ 8.23
Granted, Shares	1,119
Granted, Weighted-Average Grant Date Fair Value	$ 19.30	$ 8.23	$ 16.37
Vested, Shares	(1,897)
Vested, Weighted-Average Grant Date Fair Value	$ 8.31
Forfeited, Shares	(63)
Forfeited, Weighted-Average Grant Date Fair Value	$ 18.98
Nonvested shares, Ending Balance, Shares	1,048	1,889
Nonvested shares, Ending Balance, Weighted-Average Grant Date Fair Value	$ 19.28	$ 8.23