Employee Benefit Plans - 401(k) Plan (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Percent of maximum contribution of pretax income per employee	100.00%
Amount of maximum contribution per employee	$ 17,500
Amount of maximum catch-up contribution	5,500
Amount of matching contributions	$ 2,400,000	$ 1,500,000	$ 1,500,000
Minimum | Employee Plan 401K [Member]
Defined Benefit Plan Disclosure [Line Items]
Vesting period	4 years
Percentage of discretionary match	25.00%
Maximum percentage of eligible contribution	4.00%
Maximum | Employee Plan 401K [Member]
Defined Benefit Plan Disclosure [Line Items]
Vesting period	5
Percentage of discretionary match	50.00%
Maximum percentage of eligible contribution	5.00%