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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41502-112717

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($) quote	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Variable Interest Entity
Number of broker quotes \| quote	1
Cumulative-effect adjustment from adoption of accounting guidance			$ (122,621)
Aggregate minimum lease payments under lease obligations	$ 136,500
Retained Earnings
Variable Interest Entity
Cumulative-effect adjustment from adoption of accounting guidance		$ 352
Paid-in Capital
Variable Interest Entity
Cumulative-effect adjustment from adoption of accounting guidance		(352)	$ (12,912)
Accounting Standards Update 2016-09 \| Retained Earnings
Variable Interest Entity
Cumulative-effect adjustment from adoption of accounting guidance		400
Accounting Standards Update 2016-09 \| Paid-in Capital
Variable Interest Entity
Cumulative-effect adjustment from adoption of accounting guidance		$ (400)
Minimum
Variable Interest Entity
Withdrawal period	1 month
Minimum \| Contractual Rights to Earn Future Fee Income
Variable Interest Entity
Estimated useful lives in years	3 years
Maximum
Variable Interest Entity
Withdrawal period	3 years
Maximum \| Contractual Rights to Earn Future Fee Income
Variable Interest Entity
Estimated useful lives in years	7 years