Number of shares that have been repurchased during the period and are being held in treasury.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
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Name:	us-gaap_TreasuryStockSharesAcquired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

SHARE REPURCHASE - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Feb. 25, 2019	Jun. 04, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share Repurchase [Line Items]
Stock repurchase program, authorized amount	$ 100,000
Stock repurchase program, expiration date	Mar. 01, 2020
Purchase of company stock			$ 0	$ 181,402	$ 0
KKR Share Repurchase [Member]
Share Repurchase [Line Items]
Shares repurchased (shares)		2,418,304
Percentage of Shares Outstanding		7.10%
Purchase of company stock		$ 181,400
Discounted closing stock price		$ 73.96
Percentage of closing stock price		96.00%