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Long-Term Debt (Details Textual) | 3 Months Ended | 9 Months Ended |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |  | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended |  |
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Sep. 30, 2014 USD ($) | Sep. 30, 2013 USD ($) | Sep. 30, 2014 USD ($) | Sep. 30, 2013 USD ($) | Dec. 31, 2013 USD ($) | Sep. 30, 2014 3.00% Convertible Senior Notes due 2020 [Member] USD ($) | Jul. 30, 2014 3.00% Convertible Senior Notes due 2020 [Member] USD ($) | Sep. 30, 2014 3.00% Convertible Senior Notes due 2020 [Member] | Jun. 30, 2014 3.00% Convertible Senior Notes due 2020 [Member] USD ($) | Sep. 30, 2014 3.00% Convertible Senior Notes due 2020 [Member] USD ($) | Sep. 30, 2013 3.00% Convertible Senior Notes due 2020 [Member] USD ($) | Jun. 25, 2014 3.00% Convertible Senior Notes due 2020 [Member] USD ($) | Sep. 30, 2014 5.00% Senior Note [Member] USD ($) | Sep. 30, 2014 5.00% Senior Note [Member] USD ($) | Jun. 30, 2014 5.00% Senior Note [Member] USD ($) | Sep. 30, 2014 5.00% Senior Note [Member] USD ($) | Sep. 30, 2014 Other Real Estate Related Long Term Debt [Member] USD ($) | Dec. 31, 2013 Other Real Estate Related Long Term Debt [Member] USD ($) | Sep. 30, 2014 2.25% Convertible Senior Notes due 2036 [Member] USD ($) | Sep. 30, 2014 2.25% Convertible Senior Notes due 2036 [Member] USD ($) | Sep. 30, 2014 2.25% Convertible Senior Notes due 2036 [Member] USD ($) | Sep. 30, 2013 2.25% Convertible Senior Notes due 2036 [Member] USD ($) | Sep. 02, 2014 2.25% Convertible Senior Notes due 2036 [Member] USD ($) | Sep. 30, 2014 Two Point Two Five Percent Warrants [Member] | Sep. 30, 2014 Three Point Zero Zero Percent Notes [Member] | Sep. 30, 2014 3.00% Warrants [Member] | Sep. 30, 2014 Real Estate Related Debt [Member] USD ($) | Sep. 30, 2014 Real Estate Related Debt [Member] Minimum [Member] | Sep. 30, 2014 Real Estate Related Debt [Member] Maximum [Member] | Sep. 30, 2014 Real Estate Related Debt [Member] Toyota Motor Credit Corporation [Member] USD ($) | Sep. 30, 2014 Real Estate Related Debt [Member] Toyota Motor Credit Corporation [Member] USD ($) | Sep. 30, 2014 Real Estate Related Debt [Member] Mercedes-Benz Financial Services [Member] USD ($) | Sep. 30, 2014 Real Estate Related Debt [Member] Mercedes-Benz Financial Services [Member] USD ($) | Sep. 30, 2014 Real Estate Related Debt [Member] BMW Financial Services [Member] USD ($) | Sep. 30, 2014 Real Estate Related Debt [Member] BMW Financial Services [Member] USD ($) | Sep. 30, 2014 Real Estate Related Debt [Member] Ford Motor Credit Company [Member] | Sep. 30, 2014 Real Estate Related Debt [Member] Ford Motor Credit Company [Member] | Sep. 30, 2014 Foreign Note [Member] USD ($) | Sep. 30, 2014 Brazilian third party financial institution [Member] BRL | Sep. 30, 2014 Third-party financial institution [Member] USD ($) | Sep. 30, 2014 Third-party financial institution [Member] USD ($) | Sep. 30, 2014 Third-party financial institution [Member] Ford Motor Credit Company [Member] USD ($) | Sep. 30, 2014 Third-party financial institution [Member] Ford Motor Credit Company [Member] USD ($) | Sep. 30, 2014 Real Estate Credit Facility [Member] USD ($) | Sep. 30, 2014 Real Estate Credit Facility [Member] USD ($) | Sep. 30, 2014 Real Estate Credit Facility [Member] Minimum [Member] | Sep. 30, 2014 Real Estate Credit Facility [Member] Maximum [Member] | Sep. 30, 2014 London Interbank Offered Rate (LIBOR) [Member] Real Estate Credit Facility [Member] | Sep. 30, 2014 Federal Funds Rate [Member] Real Estate Credit Facility [Member] | Sep. 30, 2014 Fixed interest rate debt [Member] Other Real Estate Related Long Term Debt [Member] USD ($) | Dec. 31, 2013 Fixed interest rate debt [Member] Other Real Estate Related Long Term Debt [Member] USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of Convertible Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 49,500,000 |  | $ 210,400,000 |  |  |  | $ 237,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gains (Losses) on Extinguishment of Debt | (22,790,000) | 0 | (46,403,000) | 0 |  | 5,900,000 |  |  | 23,600,000 |  |  |  |  |  |  |  |  |  |  |  |  | 16,900,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Warrant Exercises |  |  |  |  |  | 6,200,000 | 26,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Short-term Debt | 6,500,000 |  | 6,500,000 |  | 800,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amortization period of underwriters fees and debt issuance costs |  |  | 8 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Original Debt Instrument Interest Rate Effective Percentage |  |  |  |  |  | 8.25% |  | 8.25% |  | 8.25% |  |  |  |  |  |  |  |  |  |  | 7.50% | 7.50% | 7.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term Debt, Percentage Bearing Fixed Interest, Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 153,900,000 | 164,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term Debt, Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 174,400,000 | 190,000,000
Assessment Period For Fair Value |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.25% | 2.25% | 2.25% |  |  | 2.25% | 3.00% | 3.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity date of of notes |  |  |  |  |  |  |  | Mar. 15, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Note agreement with a third party financial institution |  |  |  |  |  |  |  |  |  |  |  |  |  | 115,000,000 | 550,000,000 | 550,000,000 | 350,000,000 | 550,000,000 |  |  | 182,800,000 | 182,800,000 | 182,800,000 |  | 182,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional borrowings of long term debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 200,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional borrowings discount from face value |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.50% | 1.50% |  | 1.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Conversion, Converted Instrument, Shares Issued | 701,795 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Conversion, Converted Instrument, Warrants or Options Issued | 421,309 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term loans provided under credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 109,800,000 | 109,800,000 |  |  | 74,100,000 | 74,100,000 |  |  |  |  |  |
Capitalization Of Debt Issuance Costs |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,200,000 | 2,200,000 |  | 2,200,000 |  |  |  |  |  |  |  |  |  |  | 1,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,100,000 | 1,100,000 |  |  |  |  |  |
Amount available to be expanded |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 99,100,000 | 99,100,000 |  |  |  |  |  |
Unamortized debt issuance cost |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,100,000 | 2,100,000 |  | 2,100,000 |  |  |  |  |  |  |  |  |  |  | 500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 400,000 | 400,000 |  |  |  |  |  |
Interest rate under condition second |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.95% |  |  |  |  |  |  |
Interest rate under sub-condition three of condition second |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.05% |  |  |
Percentage of principal payments to make its quarterly payment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.25% |  |  |  |  |  |  |
Ending date of installments to be repaid |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Jun. 01, 2022 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Sep. 01, 2020 |  | Jan. 01, 2031 |  | Sep. 01, 2019 |  | Jan. 01, 2024 | Aug. 01, 2027 | Feb. 01, 2017 |  | Nov. 01, 2022 |  |  |  |  | Dec. 29, 2015 | Feb. 27, 2017 |  |  |  |
Redemption price percentage of principal outstanding and accrued unpaid interest |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 105.00% | 105.00% |  | 105.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Redemption price percentage of principal redeemed |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100.00% | 100.00% |  | 100.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Borrowings under amended and restated mortgage facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 200,000 |  |  |  |  |  |
Principal payments on outstanding borrowings |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9,100,000 |  |  |  |  |  |
Current maturities of long-term debt | 41,021,000 |  | 41,021,000 |  | 36,225,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10,100,000 | 10,100,000 | 1,100,000 | 1,100,000 | 4,300,000 | 4,300,000 |  |  | 4,100,000 |  | 5,500,000 | 5,500,000 | 800,000 | 800,000 | 3,100,000 | 3,100,000 |  |  |  |  |  |
Number of manufacturer-affiliated finance partners | 4 |  | 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest on real estate notes, minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.67% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest on real estate notes, maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total interest expense excluding amortization cost |  |  |  |  |  |  |  |  |  | 1,839,000 |  | 2,588,000 |  |  |  |  |  |  |  |  |  |  | 1,875,000 | 3,084,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amortization schedule |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20 years |  | 20 years |  | 15 years |  | 20 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amortization cost of the 3.00% notes, 2.25% Notes and 8.25% Notes |  |  |  |  |  |  |  |  |  | 1,810,000 | [1] | 2,410,000 | [1] |  |  |  |  |  |  |  |  |  | 5,366,000 | 5,590,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Variable Interest Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.50% | 3.35% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.00% |  |  |  | 0.50% |  |
Total borrowings |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50,200,000 | 50,200,000 | 27,600,000 | 27,600,000 | 66,700,000 | 66,700,000 |  |  | 34,700,000 | 38,000,000 | 98,800,000 | 98,800,000 | 18,600,000 | 18,600,000 | 58,800,000 | 58,800,000 |  |  |  |  |  |
Convertible Debt, Fair Value Disclosures |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 533,500,000 | 533,500,000 |  | 533,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other Real Estate Related and Long-Term Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 316,703,000 | 279,167,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of loans as per loan agreements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8 |  | 2 |  | 14 |  |  |  |  |  | 17 |  | 2 |  |  |  |  |  |  |  |  |
Borrowings Of Long Term Debt Related To Real Estate Loans |  |  | $ 65,628,000 | $ 21,105,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 |  | $ 0 |  | $ 0 |  |  | $ 6,800,000 |  |  | $ 37,900,000 |  | $ 13,800,000 |  |  |  |  |  |  |  |
[1] | Represents the incremental impact of the accounting for convertible debt as primarily codified in ASC 470, Debt

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- Definition Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Convertible Security -URI http://asc.fasb.org/extlink&oid=6509036 + Details
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- Definition The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 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 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Minimum contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 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 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 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 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12317-112629 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12355-112629 + Details
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