Economic value of matching grants.

No definition available.

Name:	plmt_EconomicValueOfMatchingGrants
Namespace Prefix:	plmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Exercise period of option after grant date.

+ References

No definition available.

+ Details

Name:	plmt_ExercisePeriodOfOptionAfterGrantDate
Namespace Prefix:	plmt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares for which vesting conditions had been met.

+ References

No definition available.

+ Details

Name:	plmt_NumberOfSharesForWhichVestingConditionsHadBeenMet
Namespace Prefix:	plmt_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of fair value used for exercise price options.

+ References

No definition available.

+ Details

Name:	plmt_PercentageOfFairValueUsedForExercisePriceOptions
Namespace Prefix:	plmt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Pretax compensation expense related to unvested restricted stock awards granted.

+ References

No definition available.

+ Details

Name:	plmt_PretaxCompensationExpenseRelatedToUnvestedRestrictedStockAwardsGranted
Namespace Prefix:	plmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Share based compensation arrangement by share based payment award exercise period.

+ References

No definition available.

+ Details

Name:	plmt_ShareBasedCompensationArrangementByShareBasedPaymentAwardExercisePeriod
Namespace Prefix:	plmt_
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based compensation arrangement by share-based payment award, non-option equity instruments, granted, value.

+ References

No definition available.

+ Details

Name:	plmt_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGrantedValue
Namespace Prefix:	plmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Share based payment arrangement number of options approved to be granted.

+ References

No definition available.

+ Details

Name:	plmt_ShareBasedPaymentArrangementNumberOfOptionsApprovedToBeGranted
Namespace Prefix:	plmt_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Share based Payment number of options exercisable after date of grant.

+ References

No definition available.

+ Details

Name:	plmt_ShareBasedPaymentNumberOfOptionsExercisableAfterDateOfGrant
Namespace Prefix:	plmt_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate number of common shares reserved for future issuance.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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 210.5-02.29)

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

+ Details

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

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Net number of non-option equity instruments granted to participants.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(c), d(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph d(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Equity Based Compensation - Additional Information (Detail) (USD $)	1 Months Ended		3 Months Ended	12 Months Ended
	Oct. 20, 2011	May 16, 2011	Jun. 16, 2011	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock granted	5 years	5 years	5 years
Vesting period of stock granted				10 years
Percentage of option exercise price of fair value of common stock				100.00%
Intrinsic value of stock options				$ 0	$ 0
Cap value of matching grants				10,000
Number of shares for which vesting conditions had been met				37,396
Number of restricted stock granted, value				90,000
Number of options approved to be granted				500,000
Number of options exercisable after date of grant				0
Duration of options exercisable after the grant date				10 years
Pretax compensation expense related to unvested restricted stock awards granted				361,000
1997 Stock Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock granted				5 years
2008 Plan [Member] \| 2008 Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Matching grants of restricted stock awarded				51,311
2011 Stock incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pretax compensation expense related to unvested restricted stock awards granted				$ 1,700,000
2011 Stock incentive Plan [Member] \| 1997 Stock Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options exercisable				0
2008 Restricted Stock Plan [Member] \| 2008 Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock granted				5 years
Non management director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, future issuance				62,500
Non management director [Member] \| 2008 Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Matching grants of restricted stock awarded				17,613
Team Member [Member] \| 2011 Stock incentive Plan [Member] \| 2008 Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Matching grants of restricted stock awarded				8,020
Director [Member] \| 2008 Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Matching grants of restricted stock awarded				2,354
Director [Member] \| 2008 Restricted Stock Plan [Member] \| 2008 Restricted Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock granted				3 years