Stock-Based Compensation and Other Benefit Plans - Employee Stock Purchase Plan and Stock-Based Compensation Expense (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award
Maximum shares employees may purchase each year, value			$ 25,000
Non-cash share-based compensation expense	$ 3,200,000	$ 4,000,000.0
Total fair value of the shares purchased under the plan	100,000	100,000
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award
Maximum number of shares that may be issued (in shares)			500,000
Percent of common stock fair market value			85.00%
Offering period			3 months
Maximum employee compensation payroll deductions may not exceed			10.00%
Maximum shares employees may purchase in any one offering period (in shares)			1,000
Non-cash share-based compensation expense	$ 100,000	$ 100,000