Contributions From Noncontrolling Interest

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Stock issued during period shares restricted stock and vesting of deferred stock.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Stock issued during period shares restricted stock contingent consideration.

+ References

No definition available.

+ Details

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- Definition

Stock issued during period value restricted stock and vesting of deferred stock.

+ References

No definition available.

+ Details

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Namespace Prefix:	md_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Stock issued during period value restricted stock contingent consideration.

+ References

No definition available.

+ Details

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Namespace Prefix:	md_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 35

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-Paragraph 1

-Subparagraph (b)

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-Topic 718

-SubTopic 20

-Section 55

-Paragraph 13

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+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

+ References

Reference 1: 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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Topic 718

-SubTopic 740

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-Paragraph 2

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

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-Topic 810

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-Paragraph 1A

-Subparagraph (a),(c)

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-Topic 810

-SubTopic 10

-Section 55

-Paragraph 4J

-URI http://asc.fasb.org/extlink&oid=35736750&loc=SL4591551-111686

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

+ Details

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

- Definition

Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 15

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-Paragraph 16

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-Topic 810

-SubTopic 10

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-Paragraph 4I

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of shares related to Restricted Stock Award forfeited during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

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-Publisher FASB

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-Topic 505

-SubTopic 10

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-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Data Type:	xbrli:sharesItemType
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Period Type:	duration

- Definition

Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ 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

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-Name Accounting Standards Codification

-Topic 505

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-Paragraph 2

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

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Period Type:	duration

- Definition

Value of stock related to Restricted Stock Awards forfeited during the period.

+ References

+ Details

Name:	us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardForfeitures
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of stock value of such awards forfeited. Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30, 31

-Article 5

+ Details

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- 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

+ Details

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Period Type:	duration

- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate 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

+ Details

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Period Type:	duration

Consolidated Statements of Equity (USD $) In Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Noncontrolling Interests [Member]
Balance at Dec. 31, 2011	$ 1,731,016	$ 978	$ 724,157	$ 1,005,881
Balance, Shares at Dec. 31, 2011		97,866
Net income (loss)	240,907us-gaap_ProfitLoss			240,907
Common stock issued under employee stock option and stock purchase plan	28,810	13	28,797
Common stock issued under employee stock option and stock purchase plan, shares		1,320
Issuance of restricted stock and vesting of deferred stock		9	(9)
Issuance of restricted stock and vesting of deferred stock, shares		930
Stock-based compensation expense	28,437		28,437
Forfeitures of restricted stock	0
Forfeitures of restricted stock, shares		(78)
Excess tax benefit related to employee stock incentive plans	6,198		6,198
Balance at Dec. 31, 2012	2,035,368	1,000	787,580	1,246,788
Balance, Shares at Dec. 31, 2012		100,038
Net income (loss)	280,517us-gaap_ProfitLoss			280,517
Common stock issued under employee stock option and stock purchase plan	28,697	14	28,683
Common stock issued under employee stock option and stock purchase plan, shares		1,331
Issuance of restricted stock and vesting of deferred stock		9	(9)
Issuance of restricted stock and vesting of deferred stock, shares		922
Stock-based compensation expense	31,288		31,288
Forfeitures of restricted stock	0
Forfeitures of restricted stock, shares		(28)
Repurchased common stock	(51,863)	(11)	(8,570)	(43,282)
Repurchased common stock, shares		(1,056)
Excess tax benefit related to employee stock incentive plans	18,981		18,981
Balance at Dec. 31, 2013	2,342,988	1,012	857,953	1,484,023
Balance, Shares at Dec. 31, 2013		101,207
Contributions from noncontrolling interests	1,025				1,025
Net income (loss)	317,203us-gaap_ProfitLoss			317,281	(78)
Common stock issued under employee stock option and stock purchase plan	42,876	13	42,863
Common stock issued under employee stock option and stock purchase plan, shares		1,412
Issuance of restricted stock and vesting of deferred stock		6	(6)
Issuance of restricted stock and vesting of deferred stock, shares		573
Issuance of restricted stock for contingent consideration	705		705
Issuance of restricted stock for contingent consideration, shares		12
Stock-based compensation expense	31,719		31,719
Forfeitures of restricted stock	0
Forfeitures of restricted stock, shares		(34)
Repurchased common stock	(488,429)	(71)	(63,836)	(424,522)
Repurchased common stock, shares		(7,140)
Excess tax benefit related to employee stock incentive plans	17,479		17,479
Balance at Dec. 31, 2014	$ 2,265,566	$ 960	$ 886,877	$ 1,376,782	$ 947
Balance, Shares at Dec. 31, 2014		96,030