Additional stock repurchased during period, shares.

No definition available.

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- Definition

Additional Stock Repurchased During Period Value

+ References

No definition available.

+ Details

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Namespace Prefix:	hca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Period Type:	duration

- Definition

Number of directors constituting board of directors minimum.

+ References

No definition available.

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Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage Of Closing Price Discount On Share Repurchase

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Purchase Price Of Common Stock Per Share

+ References

No definition available.

+ Details

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Namespace Prefix:	hca_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Reduction of non vested stock options on exercise price of share based awards.

+ References

No definition available.

+ Details

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Namespace Prefix:	hca_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Cash outflow to owners or shareholders, excluding ordinary dividends. Includes special dividends.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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Capital Stock - Additional Information (Detail) (USD $)	1 Months Ended		3 Months Ended	12 Months Ended			1 Months Ended
Capital Stock - Additional Information (Detail) (USD $)	May 31, 2014	Nov. 30, 2013	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Oct. 31, 2014
Capital Stock [Line Items]
Common stock, shares authorized			1,800,000,000us-gaap_CommonStockSharesAuthorized	1,800,000,000us-gaap_CommonStockSharesAuthorized	1,800,000,000us-gaap_CommonStockSharesAuthorized		1,800,000,000us-gaap_CommonStockSharesAuthorized
Repurchase of common stock,shares			14,028,591	14,028,591			14,028,591
Repurchase price of common stock, per share			$ 71.29
Underwritten secondary offering	14,554,628	10,656,436	14,028,591
Value of distribution per share						$ 6.50
Value of distribution				$ 0us-gaap_PaymentsOfCapitalDistribution	$ 0us-gaap_PaymentsOfCapitalDistribution	$ 3,142,000,000us-gaap_PaymentsOfCapitalDistribution
Reduction of non vested stock options on exercise price of share-based awards						$ 6.50
Minimum [Member]
Capital Stock [Line Items]
Number of directors as per the amended and restated by-laws				3
Underwritten Secondary Offering [Member]
Capital Stock [Line Items]
Repurchase price of common stock, per share	51.53	46.92
Additional shares repurchased	14,554,628	10,656,436
Underwritten secondary offering		30,000,000
Additional shares amount repurchased	750,000,000	500,000,000
Bain Capital Partners, LLC [Member]
Capital Stock [Line Items]
Repurchase of common stock,shares			7,612,921	7,612,921			7,612,921
Repurchase price of common stock, per share							$ 73.26
Percentage of discount on share repurchase							1.00%
Share repurchase Program authorized amount								$ 1,000,000,000
Additional shares repurchased			6,415,670
Purchase price of common stock, per share			$ 68.96
Bain Capital Partners, LLC [Member] \| Underwritten Secondary Offering [Member]
Capital Stock [Line Items]
Underwritten secondary offering	15,000,000