Accounts Receivable and Net Revenue - Schedule of Net Revenue (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Receivables [Abstract]
Gross revenue									$ 7,662,556md_HealthOrganizationRevenueGross	$ 6,702,484md_HealthOrganizationRevenueGross	$ 5,691,790md_HealthOrganizationRevenueGross
Contractual adjustments and uncollectibles									(5,403,437)	(4,695,232)	(3,994,924)
Hospital contract administrative fees									179,794md_HospitalContractAdministrativeFees	146,760md_HospitalContractAdministrativeFees	119,746md_HospitalContractAdministrativeFees
Net revenue	$ 650,525us-gaap_HealthCareOrganizationRevenue	$ 626,506us-gaap_HealthCareOrganizationRevenue	$ 595,544us-gaap_HealthCareOrganizationRevenue	$ 566,338us-gaap_HealthCareOrganizationRevenue	$ 567,387us-gaap_HealthCareOrganizationRevenue	$ 554,730us-gaap_HealthCareOrganizationRevenue	$ 529,180us-gaap_HealthCareOrganizationRevenue	$ 502,715us-gaap_HealthCareOrganizationRevenue	$ 2,438,913us-gaap_HealthCareOrganizationRevenue	$ 2,154,012us-gaap_HealthCareOrganizationRevenue	$ 1,816,612us-gaap_HealthCareOrganizationRevenue

Amount of revenues recognized by the entity from providing services to in-patients, outpatients, residents in facilities owned or operated by the entity, from insurance premiums, or from goods provided or services performed.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Name:	us-gaap_HealthCareOrganizationRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration