Corporation's equity in PRLP 2011 Holdings, LLC (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Related Party Transaction [Line Items]
Equity Method Investments	$ 265,524	$ 246,776
Prlp2011 Holdings Llc Joint Venture [Member]
Related Party Transaction [Line Items]
Equity Method Investments	32,883	35,969
Prlp2011 Holdings Llc Joint Venture [Member] \| Eliminations interest [Member]
Related Party Transaction [Line Items]
Equity Method Investments	6,903	13,222
Prlp2011 Holdings Llc Joint Venture [Member] \| Gross [Member]
Related Party Transaction [Line Items]
Equity Method Investments	$ 25,980	$ 22,747

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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 210.5-02.12)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=16385135&loc=d3e33749-111570

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