Capital Stock (Details) - $ / shares	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Capital Stock [Abstract]
Capital stock, shares authorized (in shares)	62,000,000
Common stock, shares authorized (in shares)	60,000,000	60,000,000
Preferred stock, shares authorized (in shares)	2,000,000	2,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Long Term Incentive Stock Option Plan 1995 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)	6,017,632
Shares under options and warrants outstanding (in shares)	0	5,000	55,000
Shares reserved upon vesting of restricted stock units (in shares)	1,719,732
Shares of common stock remaining to be granted (in shares)	1,482,368