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Sale of Equity Investment (Details) (USD $) | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2014 | Jun. 30, 2014 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Sale of Equity Investment [Abstract] |  |  |  |  |
Date of disposal |  | Apr. 17, 2014 |  |  |
Percentage of ownership interest sold (in hundredths) | 20.00%us-gaap_EquityMethodInvestmentOwnershipPercentage | 20.00%us-gaap_EquityMethodInvestmentOwnershipPercentage | 20.00%us-gaap_EquityMethodInvestmentOwnershipPercentage |  |
Book value | $ 3,000,000 us-gaap_EquityMethodInvestmentUnderlyingEquityInNetAssets | $ 3,000,000 us-gaap_EquityMethodInvestmentUnderlyingEquityInNetAssets | $ 3,000,000 us-gaap_EquityMethodInvestmentUnderlyingEquityInNetAssets |  |
Total sale price of investment | 140,000,000 us-gaap_EquityMethodInvestmentAggregateCost | 140,000,000 us-gaap_EquityMethodInvestmentAggregateCost | 140,000,000 us-gaap_EquityMethodInvestmentAggregateCost |  |
Gain on sale of equity investments | 19,401,000 us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal |  | 19,401,000 us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal | 0 us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal | 0 us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal
Proceeds of sale held in escrow | $ 5,200,000 us-gaap_EscrowDeposit | $ 5,200,000 us-gaap_EscrowDeposit | $ 5,200,000 us-gaap_EscrowDeposit |  |

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- Definition Date the entity disposed of a business or a group of assets, in CCYY-MM-DD format. + References No definition available. + Details
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- Definition This element represents the aggregate cost of investments accounted for under the equity method of accounting. + 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 210.5-02.12) -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 12 -Article 5 + Details
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 + Details
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- Definition Amount of gain (loss) on sale or disposal of an equity method investment. + References No definition available. + Details
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- Definition This item represents the entity's ownership percentage in the investee multiplied by the investee's total equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 + Details
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- Definition The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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