Financing Receivables - Schedule of Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Receivables [Abstract]
Financing receivables	$ 36,217		$ 36,217		$ 16,531
Allowance for doubtful accounts	(6,371)	$ (6,041)	(6,371)	$ (6,041)	(6,395)	$ (6,472)
Financing receivables, net of allowances	29,846		29,846		$ 10,136
Financing receivable sold	$ 0	$ 0	$ 0	$ 0

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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- Definition

Amount of decrease from sale and reclassification to held-for-sale of financing receivable.

+ References

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Amount, before allowance for credit loss, of financing receivable.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

+ References

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