Stock-Based Compensation (Restricted Stock Unit Activity) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Equity instruments other than options, weighted average grant date fair value
Weighted average grant date fair value, end of period	$ 1.01	$ 1.89
Restricted Stock Units
Equity instruments other than options, number of shares
Outstanding, beginning balance (in shares)	6	29
Forfeited	0	(6)
Converted to common stock	(2)	(17)
Outstanding, ending balance (in shares)	4	6
Vested and convertible to common stock	4
Equity instruments other than options, weighted average grant date fair value
Weighted average grant date fair value, beginning of period	$ 21.45	$ 21.21
Forfeited, weighted average grant date fair value	$ 0.00	$ 5.58
Converted to common stock, weighted average grant date fair value	$ 21.53	$ 11.61
Weighted average grant date fair value, end of period	$ 21.40	$ 21.45
Vested and convertible to common stock, weighted average grant date fair value	$ 21.06