Stock-Based Compensation (Details 2) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		1 Months Ended		3 Months Ended	1 Months Ended	3 Months Ended	1 Months Ended
	Mar. 31, 2013 Restricted stock units	Mar. 31, 2012 Restricted stock units	Nov. 30, 2008 Restricted stock units granted in 2008	Jul. 31, 2008 Restricted stock units granted in 2008	Mar. 31, 2013 Restricted stock units granted in 2008	Oct. 31, 2012 Restricted stock units granted in 2012	Mar. 31, 2013 Restricted stock units granted in 2012	Oct. 31, 2012 Restricted stock units granted in 2012 Employment agreement
Stock-Based Compensation
Restricted stock units awarded (in shares)			5,000	750,000		191,895		30,529
Vesting rights on each specified anniversary of the grant date (as a percent)					33.00%		33.00%
Number of years from grant date for first one-third vesting					10 years		1 year
Number of years from grant date for second one-third vesting					11 years		2 years
Number of years from grant date for third one-third vesting					12 years		3 years
Vesting period						3 years
Restricted stock units vested (in shares)	5,000	104,000
Restricted stock units forfeited (in shares)	0	0
Recognized stock-based compensation expense	$ 1,042	$ 361
Unrecognized stock-based compensation costs	$ 7,978
Weighted average remaining recognition period of unrecognized stock-based compensation costs	4 years