Amount of operating lease assets acquired at the acquisition date.

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Amount of operating lease liabilities assumed in business combination.

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

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Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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LEASES (Details) - USD ($) $ in Thousands	3 Months Ended
LEASES (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 31, 2020	Feb. 01, 2021	Dec. 31, 2020
LEASES
Operating lease assets			$ 45,600
Operating lease liabilities			$ 45,300
Maturities of the Company's operating lease liabilities
2021	$ 10,570
2022	11,367
2023	9,665
2024	9,530
2025	9,141
Thereafter	26,289
Total undiscounted lease payments	76,562
Less amounts representing interest	5,313
Lease liability	71,249			$ 39,874
Other information related to operating leases:
Operating lease cost	3,158	$ 1,603
Cash paid for amounts included in the measurement of operating lease liabilities	$ 3,050	$ 1,811
Weighted average remaining lease term	7 years 2 months 12 days	7 years 10 months 24 days
Weighted average discount rate	1.87%	3.25%