Stock-Based Compensation Schedule of Performance Stock Units (Details) - Performance shares - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Number of Units
Nonvested at beginning period (in shares)	41,000	148,000	140,000
Granted (in shares)	0	0	169,000
Vested (in shares)	0	(98,000)	(116,000)
Canceled (in shares)	(41,000)	(9,000)	(45,000)
Nonvested at period end (in shares)	0	41,000	148,000
2018 Performance Stock Units
Number of Units
Nonvested at beginning period (in shares)	40,599	148,000	0
Granted (in shares)	0	0	169,000
Vested (in shares)	0	(98,000)	0
Canceled (in shares)	(41,000)	(9,000)	(21,000)
Nonvested at period end (in shares)	0	40,599	148,000
2017 Performance Stock Units
Number of Units
Nonvested at beginning period (in shares)	0	0	140,493
Granted (in shares)	0	0	0
Vested (in shares)	0	0	(116,168)
Canceled (in shares)	0	0	(24,000)
Nonvested at period end (in shares)	0	0	0