Employee Benefit Plan Employee Benefit Plan (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 employee	Dec. 31, 2011	Dec. 31, 2009
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Maximum annual contribution			15.00%
Vesting percentage of employer contribution	100.00%
Costs recognized	$ 81	$ 43
Number of participants	154
Up To 3% [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contribution, percent match on employee contribution	100.00%
Employer matching contribution on salary of employee	3.00%
3% to 3.99% [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contribution, percent match on employee contribution	3.00%
3% to 3.99% [Member] | Minimum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution on salary of employee	3.00%
3% to 3.99% [Member] | Maximum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution on salary of employee	3.99%
4% to 4.99% [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contribution, percent match on employee contribution	3.50%
4% to 4.99% [Member] | Minimum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution on salary of employee	4.00%
4% to 4.99% [Member] | Maximum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution on salary of employee	4.99%
5% Or More [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer contribution, percent match on employee contribution	4.00%
Employer matching contribution on salary of employee	5.00%