Accounts Receivable	12 Months Ended
Dec. 31, 2017
Receivables [Abstract]
Accounts Receivable	Accounts receivable Approximately 21% and 16% of the Company’s net patient services accounts receivable balances as of December 31, 2017 and 2016, respectively, were more than six months old. The increase was primarily due to changes the Company made in its collection policies and procedures to improve overall collections. There were no significant balances over one year old. Accounts receivable are principally from Medicare and Medicaid programs and commercial insurance plans. Accounts receivable are reduced by an allowance for doubtful accounts. In evaluating the ultimate collectability of its accounts receivable, the Company analyzes its historical cash collection experience and trends for each payor to estimate the adequacy of the allowance for doubtful accounts and the amount of the provision for uncollectible accounts. Management regularly updates its analysis based upon the most recent information available to it to determine its current provision for uncollectible accounts and the adequacy of its allowance for doubtful accounts. For receivables associated with U.S. dialysis and related lab services covered by government payors, like Medicare, the Company receives 80% of the payment directly from Medicare as established under the government’s bundled payment system and determines an appropriate allowance for doubtful accounts and provision for uncollectible accounts on the remaining balance due depending upon the Company’s estimate of the amounts ultimately collectible from other secondary coverage sources or from the patients. For receivables associated with services to patients covered by commercial payors that are either based upon contractual terms or for non-contracted health plan coverage, the Company provides an allowance for doubtful accounts by recording a provision for uncollectible accounts based upon its historical collection experience, potential inefficiencies in its billing processes and for which collectability is determined to be unlikely. Approximately 1% of the Company’s U.S. dialysis and related lab services net accounts receivable are associated with patient pay and it is the Company’s policy to reserve 100% of the outstanding accounts receivable balances for dialysis services when those amounts due are outstanding for more than three months. During the year ended December 31, 2017, the Company’s allowance for doubtful accounts decreased by $20,498. The decrease in 2017 was primarily due to an increase in write-offs of aged balances from an increase in uninsured and underinsured uncollectible patient balances related to the U.S. dialysis and related lab business. During the year ended December 31, 2016, the Company’s allowance for doubtful accounts decreased by $12,837. The decrease in 2016 was primarily due to an increase in the write-offs of patient pay billings in the Company's U.S. dialysis business. The decrease was also due to a reduction in accounts receivable older than six months.

Accounts receivable

Approximately 21% and 16% of the Company’s net patient services accounts receivable balances as of December 31, 2017 and 2016, respectively, were more than six months old. The increase was primarily due to changes the Company made in its collection policies and procedures to improve overall collections. There were no significant balances over one year old. Accounts receivable are principally from Medicare and Medicaid programs and commercial insurance plans.

Accounts receivable are reduced by an allowance for doubtful accounts. In evaluating the ultimate collectability of its accounts receivable, the Company analyzes its historical cash collection experience and trends for each payor to estimate the adequacy of the allowance for doubtful accounts and the amount of the provision for uncollectible accounts. Management regularly updates its analysis based upon the most recent information available to it to determine its current provision for uncollectible accounts and the adequacy of its allowance for doubtful accounts.

For receivables associated with U.S. dialysis and related lab services covered by government payors, like Medicare, the Company receives 80% of the payment directly from Medicare as established under the government’s bundled payment system and determines an appropriate allowance for doubtful accounts and provision for uncollectible accounts on the remaining balance due depending upon the Company’s estimate of the amounts ultimately collectible from other secondary coverage sources or from the patients. For receivables associated with services to patients covered by commercial payors that are either based upon contractual terms or for non-contracted health plan coverage, the Company provides an allowance for doubtful accounts by recording a provision for uncollectible accounts based upon its historical collection experience, potential inefficiencies in its billing processes and for which collectability is determined to be unlikely.

Approximately 1% of the Company’s U.S. dialysis and related lab services net accounts receivable are associated with patient pay and it is the Company’s policy to reserve 100% of the outstanding accounts receivable balances for dialysis services when those amounts due are outstanding for more than three months.

During the year ended December 31, 2017, the Company’s allowance for doubtful accounts decreased by $20,498. The decrease in 2017 was primarily due to an increase in write-offs of aged balances from an increase in uninsured and underinsured uncollectible patient balances related to the U.S. dialysis and related lab business. During the year ended December 31, 2016, the Company’s allowance for doubtful accounts decreased by $12,837. The decrease in 2016 was primarily due to an increase in the write-offs of patient pay billings in the Company's U.S. dialysis business. The decrease was also due to a reduction in accounts receivable older than six months.