Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Deferred Compensation Awards - Schedule of Total Awards Granted and Number of Units Outstanding (Details) - Phantom Stock Units (PSUs) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	36 months
Units Granted (in shares)	158,242
Units Outstanding (in shares)			38,914
Amounts Paid	$ 304	$ 283
Q1 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units Granted (in shares)	8,775
Units Outstanding (in shares)			0
Amounts Paid	$ 0	0
Q1 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units Granted (in shares)	28,828
Units Outstanding (in shares)			0
Amounts Paid	$ 0	22
Q1 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units Granted (in shares)	34,830
Units Outstanding (in shares)			0
Amounts Paid	$ 29	112
Q1 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units Granted (in shares)	22,712
Units Outstanding (in shares)			1,893
Amounts Paid	$ 80	73
Q1 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units Granted (in shares)	30,907
Units Outstanding (in shares)			12,878
Amounts Paid	$ 109	76
Q1 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units Granted (in shares)	32,190
Units Outstanding (in shares)			24,143
Amounts Paid	$ 86	$ 0