STOCKHOLDERS' EQUITY - Share Repurchases (Details) - USD ($) $ / shares in Units, $ in Thousands				9 Months Ended
Dec. 18, 2017	Jun. 12, 2017	Sep. 14, 2016	Sep. 30, 2017
Equity, Class of Treasury Stock [Line Items]
Stock repurchased and retired				$ 576,000
Urban Partners II, LLC \| December 2017 Share Repurchase \| Common Stock
Equity, Class of Treasury Stock [Line Items]
Stock repurchased and retired (in shares)	14,090,909	26,181,818	3,628,116
Stock repurchased and retired	$ 310,000	$ 576,000	$ 79,819
Stock repurchased and retired (in usd per share)	$ 22	$ 22	$ 22

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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