Employee Benefit Plans	12 Months Ended
Employee Benefit Plans	Dec. 31, 2018
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee benefit plans The Company has a 401(k) retirement savings plan for substantially all of its Kidney Care employees which has been established pursuant to the applicable provisions of the Internal Revenue Code (IRC). The plan allows for employees to contribute a percentage of their base annual salaries on a tax-deferred basis not to exceed IRC limitations. Beginning in 2018, the Company implemented a 401(k) matching program under which the Company matches 50% of the employee's contribution up to 6% of the employee's salary, subject to certain limitations. The matching contributions are subject to certain eligibility and vesting conditions. For the year ended December 31, 2018, the Company accrued matching contributions totaling approximately $67,807. Prior to 2018, the Company did not provide matching contributions in connection with the 401(k) savings plan for its Kidney Care employees. The Company also maintains a voluntary compensation deferral plan, the Deferred Compensation Plan, as well as other legacy deferral plans. The Deferred Compensation Plan plan is non-qualified and permits certain employees whose annualized base salary equals or exceeds a minimum annual threshold amount as set by the Company to elect to defer all or a portion of their annual bonus payment and up to 50% of their base salary into a deferral account maintained by the Company. Total contributions to this plan in 2018, 2017 and 2016 were $3,090, $4,497 and $5,344, respectively. Deferred amounts are generally paid out in cash at the participant’s election either in the first or second year following retirement or in a specified future period at least three to four years after the deferral election was effective. During 2018, 2017 and 2016 the Company distributed $4,652, $2,789 and $1,065, respectively, to participants from its deferred compensation plans. Participants are credited with their proportional amount of annual earnings from the plans. The assets of these plans are held in rabbi trusts and as such are subject to the claims of the Company’s general creditors in the event of its bankruptcy. As of December 31, 2018 and 2017, the total fair value of assets held in these plans' trusts was $36,124 and $38,895, respectively. The assets of these plans are recorded at fair value with changes in fair value recorded in other comprehensive income prior to 2018 and recognized in "Other income, net" since January 1, 2018. Any fair value changes to the corresponding liability balance are recorded as compensation expense. See Note 5 to these consolidated financial statements. Most of the Company’s outstanding employee stock plan awards include a provision accelerating the vesting of the award in the event of a change of control. The Company also maintains a change of control protection program for its employees who do not have a significant number of stock awards, which has been in place since 2001, and which provides for cash bonuses to employees in the event of a change of control. Based on the market price of the Company’s common stock and shares outstanding at December 31, 2018, these cash bonuses would total approximately $336,530 if a change of control transaction occurred at that price and the Company’s Board of Directors did not modify the program. This amount has not been accrued at December 31, 2018, and would only be accrued upon a change of control. These change of control provisions may affect the price an acquirer would be willing to pay for the Company.