COMMON STOCK REPURCHASES AND CASH DIVIDENDS Cash Dividends (Details) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Jan. 31, 2018 Quarter $ / shares	Sep. 30, 2018 USD ($) $ / shares	Sep. 30, 2017 USD ($) $ / shares	Sep. 30, 2018 USD ($) $ / shares	Sep. 30, 2017 USD ($) $ / shares
Dividends Declared and Paid [Line Items]
Common Stock, Dividends, Number of Quarterly Distributions Declared, Current Fiscal Year | Quarter	4
Common Stock, Dividends, Per Share, Declared, Current Fiscal Year, First Quarter	$ 0.16
Common Stock, Dividends Per Share Declared, Current Fiscal Year, Second Quarter	0.16
Common Stock, Dividends Per Share Declared, Current Fiscal Year, Third Quarter	0.16
Common Stock, Dividends Per Share Declared, Current Fiscal Year, Fourth Quarter	$ 0.16
Payments of Dividends | $		$ 4,692	$ 4,164	$ 14,172	$ 12,463
Common Stock, Dividends, Per Share, Cash Paid		$ 0.16	$ 0.14	$ 0.48	$ 0.42