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Long-Term Debt (Details Textual) | 6 Months Ended |  | 3 Months Ended | 6 Months Ended |  |  | 6 Months Ended |  |  | 3 Months Ended | 6 Months Ended |  | 3 Months Ended |  | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended | 3 Months Ended | 6 Months Ended |  | 3 Months Ended | 6 Months Ended |  |  |
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Jun. 30, 2014 USD ($) | Jun. 30, 2013 USD ($) | Dec. 31, 2013 USD ($) | Jun. 30, 2014 3.00% Convertible Senior Notes due 2020 [Member] USD ($) | Jun. 30, 2014 3.00% Convertible Senior Notes due 2020 [Member] USD ($) | Jun. 30, 2013 3.00% Convertible Senior Notes due 2020 [Member] USD ($) | Jun. 25, 2014 3.00% Convertible Senior Notes due 2020 [Member] USD ($) | Dec. 31, 2013 3.00% Convertible Senior Notes due 2020 [Member] USD ($) | Jun. 30, 2014 5.00% Senior Note [Member] USD ($) | Jun. 30, 2014 Other Real Estate Related Long Term Debt [Member] USD ($) | Dec. 31, 2013 Other Real Estate Related Long Term Debt [Member] USD ($) | Jun. 30, 2014 2.25% Convertible Senior Notes due 2036 [Member] USD ($) | Jun. 30, 2014 2.25% Convertible Senior Notes due 2036 [Member] USD ($) | Jun. 30, 2013 2.25% Convertible Senior Notes due 2036 [Member] USD ($) | Dec. 31, 2013 2.25% Convertible Senior Notes due 2036 [Member] USD ($) | Jun. 30, 2014 2.25% Convertible Senior Notes due 2036 [Member] Minimum [Member] | Jun. 30, 2014 Two Point Two Five Percent Warrants [Member] | Jun. 30, 2014 Three Point Zero Zero Percent Notes [Member] | Jun. 30, 2014 2.25% Warrants [Member] | Jun. 30, 2014 3.00% Warrants [Member] | Jun. 30, 2014 3.00% Purchased Options [Member] | Jun. 30, 2014 Real Estate Related Debt [Member] USD ($) | Jun. 30, 2014 Real Estate Related Debt [Member] Minimum [Member] | Jun. 30, 2014 Real Estate Related Debt [Member] Maximum [Member] | Jun. 30, 2014 Real Estate Related Debt [Member] Toyota Motor Credit Corporation [Member] USD ($) | Jun. 30, 2014 Real Estate Related Debt [Member] Toyota Motor Credit Corporation [Member] USD ($) | Jun. 30, 2014 Real Estate Related Debt [Member] Mercedes-Benz Financial Services [Member] USD ($) | Jun. 30, 2014 Real Estate Related Debt [Member] Mercedes-Benz Financial Services [Member] USD ($) | Jun. 30, 2014 Real Estate Related Debt [Member] BMW Financial Services [Member] USD ($) | Jun. 30, 2014 Real Estate Related Debt [Member] BMW Financial Services [Member] USD ($) | Jun. 30, 2014 Real Estate Related Debt [Member] Ford Motor Credit Company [Member] | Jun. 30, 2014 Real Estate Related Debt [Member] Ford Motor Credit Company [Member] | Jun. 30, 2014 Foreign Note [Member] USD ($) | Jun. 30, 2014 Brazilian third party financial institution [Member] BRL | Jun. 30, 2014 Third-party financial institution [Member] USD ($) | Jun. 30, 2014 Third-party financial institution [Member] USD ($) | Jun. 30, 2014 Third-party financial institution [Member] Ford Motor Credit Company [Member] USD ($) | Jun. 30, 2014 Third-party financial institution [Member] Ford Motor Credit Company [Member] USD ($) | Jun. 30, 2014 Real Estate Credit Facility [Member] USD ($) | Jun. 30, 2014 Real Estate Credit Facility [Member] USD ($) | Jun. 30, 2014 Real Estate Credit Facility [Member] Minimum [Member] | Jun. 30, 2014 Real Estate Credit Facility [Member] Maximum [Member] | Jun. 30, 2014 2.25% Purchased Options [Member] | Jun. 30, 2014 London Interbank Offered Rate (LIBOR) [Member] Real Estate Credit Facility [Member] | Jun. 30, 2014 Federal Funds Rate [Member] Real Estate Credit Facility [Member] | Jun. 30, 2014 Fixed interest rate debt [Member] Other Real Estate Related Long Term Debt [Member] USD ($) | Dec. 31, 2013 Fixed interest rate debt [Member] Other Real Estate Related Long Term Debt [Member] USD ($) | Jul. 03, 2014 Subsequent Event [Member] 3.00% Purchased Options [Member]
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amortization period of underwriters fees and debt issuance costs | 8 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Original Debt Instrument Interest Rate Effective Percentage |  |  |  | 8.25% | 8.25% |  |  |  |  |  |  |  |  | 7.50% | 7.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term Debt, Percentage Bearing Fixed Interest, Amount |  |  |  |  |  |  |  |  |  |  |  | $ 160,200,000 | $ 164,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term Debt, Fair Value |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 185,800,000 | 190,000,000 |
Assessment Period For Fair Value |  |  |  | 10 years |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt interest rate |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.25% | 2.25% |  |  |  |  |  | 2.25% | 3.00% |  | 3.00% | 3.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.25% |  |  |  |  |
Dividend threshold for adjustment to conversion price |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.14 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Minimum trading days for conversion price |  |  |  |  |  |  |  |  |  |  |  |  |  | 20 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum trading days for conversion price under redemption condition |  |  |  |  |  |  |  |  |  |  |  |  |  | 30 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Minimum percentage of conversion price to be considered to redeem all or part of the notes |  |  |  |  |  |  |  |  |  |  |  |  |  | 130.00% |  |  |  |  |  | 130.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Initial conversion price per share |  |  |  | $ 48.26 |  |  |  |  |  |  |  |  |  | $ 77.05 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of business days after trading day period |  |  |  | 5 days |  |  |  |  |  |  |  |  |  | 5 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of trading days as observation period for determined weighted price of company's common stock |  |  |  | 10 days |  |  |  |  |  |  |  |  |  | 10 days |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of note to be considered under conversion rate |  |  |  | 1,000 | 1,000 |  |  |  |  |  |  |  |  | 1,000 | 1,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum closing sale price under condition two |  |  |  | 98.00% |  |  |  |  |  |  |  |  |  | 98.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Conversion value in cash |  |  |  | 28,500,000 |  |  |  |  |  |  |  |  |  | 76,200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of common shares to be issued for per $ 1,000 principal amount of note |  |  |  | 26.9352 |  |  |  |  |  |  |  |  |  | 16.8653 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Conversion price per share |  |  |  | $ 37.13 | $ 37.13 |  |  |  |  |  |  |  |  | $ 59.27 | $ 59.27 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price per common stock under warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 80.09 | 54.55 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum number of shares of common stock required to be issued under warrants |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3,100,000 |  |  |  |  | 600,000
purchase options settled |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,500,000
Maturity date of of notes |  |  |  | Mar. 15, 2020 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Note agreement with a third party financial institution |  |  |  | 22,550,000 | 22,550,000 |  |  |  | 115,000,000 | 115,000,000 | 350,000,000 |  |  | 182,753,000 | 182,753,000 |  |  |  | 182,753,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term loans provided under credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 90,600,000 | 90,600,000 |  |  | 74,100,000 | 74,100,000 |  |  |  |  |  |  |  |
Capitalization Of Debt Issuance Costs |  |  |  |  |  |  |  |  |  |  | 1,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,300,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,100,000 | 1,100,000 |  |  |  |  |  |  |  |
Amount available to be expanded |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 99,100,000 | 99,100,000 |  |  |  |  |  |  |  |
Unamortized debt issuance cost |  |  |  | 44,000 | 44,000 |  |  |  |  | 236,000 | 1,500,000 |  |  | 27,000 | 27,000 |  |  |  | 33,000 |  |  |  |  |  |  | 600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 500,000 | 500,000 |  |  |  |  |  |  |  |
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 |  | Dec. 01, 2030 |  | Sep. 01, 2019 |  | Jan. 01, 2024 | Aug. 01, 2027 | Feb. 01, 2017 |  | Nov. 01, 2022 |  |  |  |  | Dec. 29, 2015 | Feb. 27, 2017 |  |  |  |  |  |
Borrowings under amended and restated mortgage facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 200,000 |  |  |  |  |  |  |  |
Principal payments on outstanding borrowings |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,600,000 |  |  |  |  |  |  |  |
Current maturities of long-term debt | 30,516,000 |  | 36,225,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,000,000 | 7,000,000 | 1,700,000 | 1,700,000 | 4,200,000 | 4,200,000 |  |  | 4,000,000 |  | 4,600,000 | 4,600,000 | 800,000 | 800,000 | 3,500,000 | 3,500,000 |  |  |  |  |  |  |  |
Interest on real estate notes, minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.67% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest on real estate notes, maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total interest expense excluding amortization cost |  |  |  |  | 1,679,000 |  | 1,725,000 |  |  |  |  |  |  |  | 2,056,000 |  | 2,056,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amortization schedule |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20 years |  | 20 years |  | 15 years |  | 11 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amortization cost of the 3.00% notes, 2.25% Notes and 8.25% Notes |  |  |  |  | 1,693,000 | [1] | 1,588,000 | [1] |  |  |  |  |  |  | 3,998,000 | [2] | 3,689,000 | [2] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Variable Interest Rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.90% | 3.35% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.00% |  |  |  |  | 0.50% |  |  |
Total borrowings |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50,800,000 | 50,800,000 | 44,700,000 | 44,700,000 | 68,100,000 | 68,100,000 |  |  | 30,200,000 | 22,000,000 | 81,200,000 | 81,200,000 | 18,900,000 | 18,900,000 | 66,300,000 | 66,300,000 |  |  |  |  |  |  |  |
Convertible Debt, Fair Value Disclosures |  |  |  | 52,900,000 | 52,900,000 |  |  |  |  | 231,200,000 | 351,800,000 |  |  | 261,200,000 | 261,200,000 |  |  |  | 231,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other Real Estate Related and Long-Term Debt |  |  |  |  |  |  |  |  |  |  |  | 307,738,000 | 279,167,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of loans as per loan agreements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8 |  | 3 |  | 14 |  |  |  |  |  | 14 |  | 2 |  |  |  |  |  |  |  |  |  |  |
Borrowings Of Long Term Debt Related To Real Estate Loans | $ 32,559,000 | $ 6,008,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 |  | $ 0 |  | $ 0 |  |  | $ 0 |  |  | $ 18,700,000 |  | $ 13,800,000 |  |  |  |  |  |  |  |  |  |
[1] | Represents the incremental impact of the accounting for convertible debt as primarily codified in ASC 470, Debt
[2] | Represents the incremental impact of the accounting for convertible debt as primarily codified in ASC 470, Debt.

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- Definition Amortization schedule of loan agreement. + References No definition available. + Details
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- Definition Borrowings of long term debt related to real estate loans. + References No definition available. + Details
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- Definition Borrowings under amended and restated mortgage facility. + References No definition available. + Details
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- Definition Conversion price per share. + References No definition available. + Details
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- Definition Conversion value in cash. + References No definition available. + Details
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- Definition Dividend threshold for adjustment to conversion price. + References No definition available. + Details
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- Definition Initial conversion price per share. + References No definition available. + Details
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- Definition Maximum amount of term loan to be expand under real estate credit facility. + References No definition available. + Details
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- Definition Maximum closing sale price under condition two. + References No definition available. + Details
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- Definition Maximum number of shares of common stock required to be issued under warrants. + References No definition available. + Details
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- Definition Minimum percentage of conversion price to be considered to redeem all or part of the notes. + References No definition available. + Details
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- Definition Number of common shares to be issued for per one thousand principal amount of note. + References No definition available. + Details
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- Definition Percentage of quarterly principal payments of outstanding principal. + References No definition available. + Details
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- Definition Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399 Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 5 + Details
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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 Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 5 + Details
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