Condensed consolidating financial statements - Condensed Consolidating Balance Sheets (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2017
Condensed Balance Sheet Statements Captions [Line Items]
Cash and cash equivalents	$ 1,253,256	$ 323,038
Restricted cash and equivalents	103,885	92,382
Accounts receivable, net	1,901,225	1,858,608
Other current assets	740,352	760,566
Current assets held for sale, net	0	5,389,565
Total current assets	3,998,718	8,424,159
Property and equipment, net	3,419,238	3,393,669
Operating lease right-of-use asset	2,781,288	0
Intangible assets, net	117,666	118,846
Investments in and advances to affiliates, net	0	0
Other long-term assets and investments	369,261	331,618
Goodwill	6,765,659	6,841,960	$ 6,610,279
Total assets	17,451,830	19,110,252
Current liabilities	2,206,640	3,647,402
Current liabilities held for sale	0	1,243,759
Intercompany liabilities, net	0	0
Long-term operating lease liabilities	2,682,125	0
Long-term debt and other long-term liabilities	8,754,483	9,186,052
Noncontrolling interests subject to put provisions	1,296,059	1,124,641
Total DaVita Inc. shareholders' equity	2,318,576	3,703,442
Noncontrolling interests not subject to put provisions	193,947	204,956
Total equity	2,512,523	3,908,398
Total liabilities and equity	17,451,830	19,110,252
Consolidating adjustments
Condensed Balance Sheet Statements Captions [Line Items]
Cash and cash equivalents	0	0
Restricted cash and equivalents	0	0
Accounts receivable, net	0	0
Other current assets	0	0
Current assets held for sale, net		0
Total current assets	0	0
Property and equipment, net	0	0
Operating lease right-of-use asset	0
Intangible assets, net	0	0
Investments in and advances to affiliates, net	(20,650,469)	(22,217,544)
Other long-term assets and investments	0	0
Goodwill	0	0
Total assets	(20,650,469)	(22,217,544)
Current liabilities	0	0
Current liabilities held for sale		0
Intercompany liabilities, net	(6,570,166)	(8,659,837)
Long-term operating lease liabilities	0
Long-term debt and other long-term liabilities	0	0
Noncontrolling interests subject to put provisions	554,759	526,566
Total DaVita Inc. shareholders' equity	(14,080,303)	(13,557,707)
Noncontrolling interests not subject to put provisions	(554,759)	(526,566)
Total equity	(14,635,062)	(14,084,273)
Total liabilities and equity	(20,650,469)	(22,217,544)
DaVita Inc. | Reportable Legal Entities
Condensed Balance Sheet Statements Captions [Line Items]
Cash and cash equivalents	831,514	60,653
Restricted cash and equivalents	0	1,005
Accounts receivable, net	0	0
Other current assets	161,548	37,185
Current assets held for sale, net		0
Total current assets	993,062	98,843
Property and equipment, net	515,952	491,462
Operating lease right-of-use asset	103,621
Intangible assets, net	85	153
Investments in and advances to affiliates, net	10,465,104	13,522,198
Other long-term assets and investments	96,953	53,385
Goodwill	0	0
Total assets	12,174,777	14,166,041
Current liabilities	313,934	1,945,943
Current liabilities held for sale		0
Intercompany liabilities, net	922,571	0
Long-term operating lease liabilities	131,743
Long-term debt and other long-term liabilities	7,746,653	7,918,581
Noncontrolling interests subject to put provisions	741,300	598,075
Total DaVita Inc. shareholders' equity	2,318,576	3,703,442
Noncontrolling interests not subject to put provisions	0	0
Total equity	2,318,576	3,703,442
Total liabilities and equity	12,174,777	14,166,041
Guarantor subsidiaries | Reportable Legal Entities
Condensed Balance Sheet Statements Captions [Line Items]
Cash and cash equivalents	213,635	1,232
Restricted cash and equivalents	14,444	12,048
Accounts receivable, net	1,221,169	1,204,122
Other current assets	455,616	565,974
Current assets held for sale, net		0
Total current assets	1,904,864	1,783,376
Property and equipment, net	1,576,140	1,584,321
Operating lease right-of-use asset	1,592,472
Intangible assets, net	34,493	42,896
Investments in and advances to affiliates, net	7,110,581	6,196,801
Other long-term assets and investments	91,115	90,037
Goodwill	4,818,001	4,806,939
Total assets	17,127,666	14,504,370
Current liabilities	1,233,054	1,217,526
Current liabilities held for sale		0
Intercompany liabilities, net	3,074,785	2,498,545
Long-term operating lease liabilities	1,508,343
Long-term debt and other long-term liabilities	664,470	687,443
Noncontrolling interests subject to put provisions	0	0
Total DaVita Inc. shareholders' equity	10,647,014	10,100,856
Noncontrolling interests not subject to put provisions	0	0
Total equity	10,647,014	10,100,856
Total liabilities and equity	17,127,666	14,504,370
Non- Guarantor subsidiaries | Reportable Legal Entities
Condensed Balance Sheet Statements Captions [Line Items]
Cash and cash equivalents	208,107	261,153
Restricted cash and equivalents	89,441	79,329
Accounts receivable, net	680,056	654,486
Other current assets	123,188	157,407
Current assets held for sale, net		5,389,565
Total current assets	1,100,792	6,541,940
Property and equipment, net	1,327,146	1,317,886
Operating lease right-of-use asset	1,085,195
Intangible assets, net	83,088	75,797
Investments in and advances to affiliates, net	3,074,784	2,498,545
Other long-term assets and investments	181,193	188,196
Goodwill	1,947,658	2,035,021
Total assets	8,799,856	12,657,385
Current liabilities	659,652	483,933
Current liabilities held for sale		1,243,759
Intercompany liabilities, net	2,572,810	6,161,292
Long-term operating lease liabilities	1,042,039
Long-term debt and other long-term liabilities	343,360	580,028
Noncontrolling interests subject to put provisions	0	0
Total DaVita Inc. shareholders' equity	3,433,289	3,456,851
Noncontrolling interests not subject to put provisions	748,706	731,522
Total equity	4,181,995	4,188,373
Total liabilities and equity	$ 8,799,856	$ 12,657,385