Other Assets and Liabilities - Other Non-Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Other Non-Current Liabilities:
Customer allowances	$ 1,210	$ 981
Unrecognized tax benefits	3,143	6,465
Guarantee to Deerfield	1,256	1,372
Other	55	55
Total	$ 5,664	$ 8,873

Noncurrent regulatory liabilities generally represent obligations to make refunds to customers for various reasons including overpayment.

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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Amount of long-term debt classified as other.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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