Represents the period after a change of control within which, if employment of the individual is either terminated without cause or due to resignation for good reason, the equity award will be fully vested, as defined under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

STOCK-BASED COMPENSATION - Performance Share Awards – Peer Group Market Condition Vesting (Details) - USD ($) $ / shares in Units, $ in Millions							12 Months Ended
	Feb. 11, 2020	Jan. 23, 2019	Jan. 24, 2018	Aug. 04, 2017	Feb. 03, 2017	Feb. 26, 2016	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Peer Group Market Condition Vesting \| Equity Award Agreements
Award agreements
Period after change of control for equity award to fully vest upon termination of employment without cause or resignation				24 months
Performance Shares \| Peer Group Market Condition Vesting
Stock-based compensation
Performance period		3 years	3 years		3 years
Vested	14,214
Shares
Outstanding (in shares)							28,080	12,635
Granted (in shares)		21,195	15,445		12,635		21,195	15,445	12,635
Vested (in shares)	(14,214)
Outstanding (in shares)							49,275	28,080	12,635
Weighted Average Fair Value
Outstanding (in dollars per share)							$ 66.29	$ 55.66
Granted (in dollars per share)							64.66	74.99	$ 55.66
Outstanding (in dollars per share)							$ 65.59	$ 66.29	$ 55.66
Compensation cost
Unrecognized compensation cost							$ 1.3
Weighted average period of recognition of unrecognized compensation cost							1 year 8 months 12 days
Performance Shares \| Minimum \| Peer Group Market Condition Vesting
Stock-based compensation
Vesting percentage		0.00%	0.00%		0.00%
Performance Shares \| Maximum \| Peer Group Market Condition Vesting
Stock-based compensation
Vesting percentage		150.00%	150.00%		150.00%
Stock Option Awards \| Amended and Restated 2010 Equity Incentive Plan \| Equity Award Agreements
Award agreements
Period after change of control for equity award to fully vest upon termination of employment without cause or resignation				24 months
Stock Option Awards \| Mr. Albright \| Amended and Restated 2010 Equity Incentive Plan \| Vesting on designated anniversary dates
Stock-based compensation
Vesting percentage						67.00%
Stock Option Awards \| Mr. Albright \| Amended and Restated 2010 Equity Incentive Plan \| Immediate vesting
Stock-based compensation
Vesting percentage						33.00%