EQUITY AND MEZZANINE EQUITY - Share Repurchase Program (Details) - Share Repurchase Program - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share Repurchase Program
Shares repurchased (in shares)	116	38	290	67
Aggregate cost of common shares repurchased	$ 6,862	$ 1,972	$ 15,667	$ 3,415
Average price per share (in dollars per share)	$ 59.12	$ 52.23	$ 54.03	$ 51.26

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Period Type:	duration