Stock-Based Compensation (Details 1) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary of nonvested stock awards granted
No. of Shares Granted	536,093	0
Weighted Average Grant Date Fair Value	$ 7.64
2008 Equity Incentive Plan [Member]
Summary of nonvested stock awards granted
Vesting Period	3 years
Director Group [Member]
Summary of nonvested stock awards granted
Vesting Period	1 year or less	1 year or less	1year or less
Weighted Average Grant Date Fair Value	$ 3.89	$ 4.06	$ 2.53
Director Group [Member] | 2008 Equity Incentive Plan [Member] | Restricted Stock and Restricted Stock Units [Member]
Summary of nonvested stock awards granted
Grantee Type	Director group	Director group	Director group
No. of Shares Granted	56,261	65,801	51,276
Vesting Period	1 year or less	1 year or less	1 year or less
Weighted Average Grant Date Fair Value	$ 7.55	$ 7.23	$ 4.20
Director group [Member]
Summary of nonvested stock awards granted
Vesting Period		3 years
Weighted Average Grant Date Fair Value		$ 3.98
Director group [Member] | 2008 Equity Incentive Plan [Member] | Restricted Stock and Restricted Stock Units [Member]
Summary of nonvested stock awards granted
Grantee Type		Director group
No. of Shares Granted		17,237
Vesting Period		3 years
Weighted Average Grant Date Fair Value		$ 6.34
Director [Member]
Summary of nonvested stock awards granted
Vesting Period	3 years		3 years
Weighted Average Grant Date Fair Value	$ 4.25		$ 4.00
Director [Member] | 2008 Equity Incentive Plan [Member]
Summary of nonvested stock awards granted
Vesting Period	1 year
Director [Member] | 2008 Equity Incentive Plan [Member] | Restricted Stock and Restricted Stock Units [Member]
Summary of nonvested stock awards granted
Grantee Type	Director		Director
No. of Shares Granted	8,546		8,546
Vesting Period	3 years		3 years
Weighted Average Grant Date Fair Value	$ 7.72		$ 5.39
Employee group [Member]
Summary of nonvested stock awards granted
Vesting Period	3 years	2 years	3 years
Weighted Average Grant Date Fair Value	$ 4.12	$ 3.72	$ 2.68
Employee group [Member] | 2008 Equity Incentive Plan [Member] | Restricted Stock and Restricted Stock Units [Member]
Summary of nonvested stock awards granted
Grantee Type	Employee group	Employee group	Employee group
No. of Shares Granted	426,286	60,000	600,010
Vesting Period	3 years	2 years	3 years
Weighted Average Grant Date Fair Value	$ 7.55	$ 6.09	$ 4.02
Employee group [Member]
Summary of nonvested stock awards granted
Vesting Period		3 years
Weighted Average Grant Date Fair Value		$ 4.33
Employee group [Member] | 2008 Equity Incentive Plan [Member] | Restricted Stock and Restricted Stock Units [Member]
Summary of nonvested stock awards granted
Grantee Type		Employee group
No. of Shares Granted		455,064
Vesting Period		3 years
Weighted Average Grant Date Fair Value		$ 7.41
Employee inducement [Member]
Summary of nonvested stock awards granted
Vesting Period	3 years
Weighted Average Grant Date Fair Value	$ 4.58	$ 3.13
Employee inducement [Member] | Maximum [Member]
Summary of nonvested stock awards granted
Vesting Period		4 years
Employee inducement [Member] | Minimum [Member]
Summary of nonvested stock awards granted
Vesting Period		3 years
Employee inducement [Member] | 2008 Equity Incentive Plan [Member] | Restricted Stock and Restricted Stock Units [Member]
Summary of nonvested stock awards granted
Grantee Type	Employee inducement	Employee inducement
No. of Shares Granted	45,000	120,000
Vesting Period	3 years
Weighted Average Grant Date Fair Value	$ 8.54	$ 5.66
Employee inducement [Member] | 2008 Equity Incentive Plan [Member] | Restricted Stock and Restricted Stock Units [Member] | Maximum [Member]
Summary of nonvested stock awards granted
Vesting Period		4 years
Employee inducement [Member] | 2008 Equity Incentive Plan [Member] | Restricted Stock and Restricted Stock Units [Member] | Minimum [Member]
Summary of nonvested stock awards granted
Vesting Period		3 years