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Stock-Based Compensation - Narrative (Details) - shares	12 Months Ended
Stock-Based Compensation - Narrative (Details) - shares	Dec. 31, 2019	Dec. 31, 2013	Dec. 31, 2012
Members of the Board
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share initially made available for awards (in shares)			830,925
Additional shares added to the plan (in shares)		700,000
Share available for issuance of future awards (in shares)	16,174