LEASES - Operating Lease Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Operating Lease Maturity, ASC 842
Remainder of current year	$ 1,977
Year ending December 31, 2020	8,066
Year ending December 31, 2021	6,032
Year ending December 31, 2022	5,495
Year ending December 31, 2023	5,191
Thereafter	7,287
Total lease payments	34,048
Less: Interest	3,887
Present value of lease liabilities	$ 30,161
Operating Lease Maturity, ASC 840
Year ending December 31, 2019		$ 4,406
Year ending December 31, 2020		3,188
Year ending December 31, 2021		1,094
Year ending December 31, 2022		736
Year ending December 31, 2023		228
Total		$ 9,652

Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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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.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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