SCHEDULE II - CONDENSED FINANCIAL INFORMATION OF REGISTRANT (Details 8) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012
Interest rate floor and reinsurance rate cap agreements
Combined liability for interest rate floor and reinsurance rate cap agreements	$ 2.0	$ 17.1
Unrealized gains (losses) on interest rate floor and reinsurance rate cap agreements	$ 15.1	$ (10.7)

Represents the unrealized gain (loss) on interest rate floor and reinsurance rate cap agreements included in the statements of income of the entity.

No definition available.

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