Note 6 - Long-Term Debt (Details) (USD $)	3 Months Ended
Mar. 31, 2014 acre	Dec. 31, 2013
Note 6 - Long-Term Debt (Details) [Line Items]
Long-term Debt	$ 50,600,000	$ 49,000,000
May 1, 2015 [Member] \| American AgCredit Term Loan [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument Amount of Principal Balance that could be Outstanding at Specified Date	3,000,000
May 1, 2016 [Member] \| American AgCredit Term Loan [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument Amount of Principal Balance that could be Outstanding at Specified Date	2,000,000
London Interbank Offered Rate (LIBOR) [Member] \| Wells Fargo Revolving Loans [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.65%
London Interbank Offered Rate (LIBOR) [Member] \| American AgCredit Term Loan [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Basis Spread on Variable Rate	4.00%
Wells Fargo Revolving Loans [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	32,700,000
Pledged Assets Not Separately Reported Area of Real Estate (in Acres)	880
Debt Instrument, Covenant Required Liabilities	175,000,000
Line of Credit Facility, Commitment Fee Amount	0
Long-term Debt	30,600,000	29,000,000
American AgCredit Term Loan [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Pledged Assets Not Separately Reported Area of Real Estate (in Acres)	3,100
Long-term Debt	20,000,000	20,000,000
Debt Instrument, Interest Rate, Stated Percentage	5.00%	5.00%
Debt Instrument Basis Spread on Variable Rate after Tiered Reduction	0.0375
Debt Instrument Mandatory Principal Repayments as Percentage Net Proceeds of Sale of Real Estate Property Pledged as Collateral	100.00%
Minimum [Member] \| Wells Fargo Revolving Loans [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Covenant Required Liabilities	3,000,000
Minimum [Member] \| American AgCredit Term Loan [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Long-term Debt	15,000,000
Debt Instrument, Interest Rate, Stated Percentage	1.00%
Debt Instrument, Covenant Required Liquidity	3,000,000
Debt Instrument Mandatory Principal Repayments as Percentage Net Proceeds of Sale of Non Collateralized Real Property	60.00%
Minimum [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Covenant Required Liquidity	3,000,000
Maximum [Member] \| American AgCredit Term Loan [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Covenant Required Liabilities	175,000,000
Debt Instrument Mandatory Principal Repayments as Percentage Net Proceeds of Sale of Non Collateralized Real Property	75.00%
Maximum [Member]
Note 6 - Long-Term Debt (Details) [Line Items]
Debt Instrument, Covenant Required Liabilities	$ 175,000,000

The principal balance amount the entity is required to pay down to by a specified date.

No definition available.

Name:	mlp_DebtInstrumentAmountOfPrincipalBalanceThatCouldBeOutstandingAtSpecifiedDate
Namespace Prefix:	mlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The percentage points added to the reference rate to compute the variable rate on the debt instrument after tiered reductions.

+ References

No definition available.

+ Details

Name:	mlp_DebtInstrumentBasisSpreadOnVariableRateAfterTieredReduction
Namespace Prefix:	mlp_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the amount of liabilities required to be maintained under financial covenants.

+ References

No definition available.

+ Details

Name:	mlp_DebtInstrumentCovenantRequiredLiabilities
Namespace Prefix:	mlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the amount of liquidity required to be maintained under financial covenants.

+ References

No definition available.

+ Details

Name:	mlp_DebtInstrumentCovenantRequiredLiquidity
Namespace Prefix:	mlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the amount of mandatory principal repayment as a percentage of the net proceeds of the sale of non-collateralized real property.

+ References

No definition available.

+ Details

Name:	mlp_DebtInstrumentMandatoryPrincipalRepaymentsAsPercentageNetProceedsOfSaleOfNonCollateralizedRealProperty
Namespace Prefix:	mlp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the amount of mandatory principal repayment as a percentage of the net proceeds of the sale of any real property pledged as collateral.

+ References

No definition available.

+ Details

Name:	mlp_DebtInstrumentMandatoryPrincipalRepaymentsAsPercentageNetProceedsOfSaleOfRealEstatePropertyPledgedAsCollateral
Namespace Prefix:	mlp_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	mlp_Note6LongTermDebtDetailsLineItems
Namespace Prefix:	mlp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Area of real estate owned but transferred to serve as collateral for the payment of the related debt obligation, primarily a secured borrowing or repurchase agreement, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

No definition available.

+ Details

Name:	mlp_PledgedAssetsNotSeparatelyReportedAreaOfRealEstate
Namespace Prefix:	mlp_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of the fee for available but unused credit capacity under the credit facility.

+ 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 210.5-02.19(b),22(b))

-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 19, 22

-Article 5

+ Details

Name:	us-gaap_LineOfCreditFacilityCommitmentFeeAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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