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

No definition available.

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

- Definition

The number of optional extension periods available under credit facilities that the company has.

+ References

No definition available.

+ Details

Name:	mlp_NumberOfOptionalExtensionPeriods
Namespace Prefix:	mlp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The duration of the optional extension period provided under the terms of a credit facility the company holds.

+ References

No definition available.

+ Details

Name:	mlp_OptionalExtensionPeriodsDurationOfExtension
Namespace Prefix:	mlp_
Data Type:	xbrli:durationItemType
Balance Type:	na
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

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

+ Details

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

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. 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 FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: 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 3: 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

+ Details

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

- Details

Name:	us-gaap_CreditFacilityAxis=mlp_FirstHawaiianBankRevolvingLineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note 1 - Basis of Presentation (Details Textual) $ in Thousands	Aug. 05, 2016 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)
First Hawaiian Bank Revolving Line of Credit [Member]
Number of Optional Extension Periods	2
Line of Credit Facility, Maximum Borrowing Capacity	$ 27,000
Optional Extension Periods, Duration of Extension	1 year
Minimum [Member]
Debt Instrument, Covenant Required Liquidity		$ 500
Maximum [Member]
Debt Instrument, Covenant Required Liquidity		45,000
Long-term Debt	$ 26,400	$ 24,500	$ 40,565