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Share Based Compensation, 401(k) Plan and Deferred Compensation (Textual) (Details) |  |  |  |  | 12 Months Ended |  |  |  |
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May 24, 2016 shares | Mar. 08, 2016 Installment shares | Feb. 22, 2016 shares | Feb. 01, 2016 shares | Dec. 31, 2016 USD ($) shares | Dec. 31, 2015 USD ($) shares | Dec. 31, 2014 USD ($) | Feb. 05, 2016 $ / shares | Feb. 23, 2015 shares | Mar. 12, 2014 shares | Mar. 11, 2014 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | shares |  |  |  |  | 2,377,778 | 2,624,067 |  |  |  |  |
Share-based compensation expense |  |  |  |  | $ 5,600,000 | $ 7,300,000 | $ 6,100,000 |  |  |  |
Share-based compensation expense, capitalized |  |  |  |  | 1,000,000 | 1,900,000 | 1,700,000 |  |  |  |
Defined Contribution Plan, Employer Discretionary Contribution Amount |  |  |  |  | $ 400,000 | $ 400,000 | 400,000 |  |  |  |
Defined Contribution Plan, Maximum Annual Contribution Per Employee, Percent |  |  |  |  | 100.00% |  |  |  |  |  |
Number of shares to be issued under deferred compensation plan included in total shares outstanding | shares |  |  |  |  | 800,000 | 700,000 |  |  |  |  |
Stock Option [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number | shares |  |  |  |  | 2,377,778 |  |  |  |  |  |
Share-based compensation expense |  |  |  |  | $ 0 | $ 0 |  |  |  |  |
Share-based compensation expense, capitalized |  |  |  |  | 0 | 0 |  |  |  |  |
Restricted Share Awards [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  |  |  | 2,600,000 | 2,400,000 | 2,700,000 |  |  |  |
Share-based compensation expense, capitalized |  |  |  |  | $ 400,000 | $ 700,000 | 600,000 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number | shares |  |  |  |  | 488,604 | 506,147 |  |  |  |  |
Vesting period |  |  |  |  | 3 years |  |  |  |  |  |
Unrecognized compensation expenses |  |  |  |  | $ 2,100,000 |  |  |  |  |  |
Weighted average period over which options will be recognized |  |  |  |  | 1 year 4 months 24 days |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  |  |  |  | three years from the initial grant dates |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares |  |  |  |  | 227,845 |  |  |  |  |  |
Voluntary Termination Of Employment Terms |  |  |  |  | after reaching at least age 57 and accumulating at least 15 years of service with the Company |  |  |  |  |  |
Accumulated Service Period For Voluntary Termination |  |  |  |  | 15 years |  |  |  |  |  |
Restricted Share Awards [Member] | Executive Officer [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Voluntary Termination of Employment Age Limit |  |  |  |  | 57 years |  |  |  |  |  |
Restricted Share Awards [Member] | Non-Officer Employees [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares |  | 54,168 |  |  |  |  |  |  |  |  |
Number of Vesting Installments | Installment |  | 3 |  |  |  |  |  |  |  |  |
Restricted Share Awards [Member] | Cliff Vest [Member] | Executive Officer [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares |  |  | 141,358 |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award, Vesting Date |  |  | Apr. 15, 2019 |  |  |  |  |  |  |  |
Restricted Share Awards [Member] | Vest Ratably Over Three Years [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Vesting period | 3 years |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares | 32,319 |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights |  |  |  |  | ratably over three years |  |  |  |  |  |
Restricted Share Awards [Member] | Installment One [Member] | Non-Officer Employees [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award, Vesting Date |  | Apr. 15, 2017 |  |  |  |  |  |  |  |  |
Restricted Share Awards [Member] | Installment Two [Member] | Non-Officer Employees [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award, Vesting Date |  | Apr. 15, 2018 |  |  |  |  |  |  |  |  |
Restricted Share Awards [Member] | Installment Three [Member] | Non-Officer Employees [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award, Vesting Date |  | Apr. 15, 2019 |  |  |  |  |  |  |  |  |
Restricted Performance Share Units Plan [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  |  |  | $ 2,800,000 | $ 4,200,000 | 3,200,000 |  |  |  |
Share-based compensation expense, capitalized |  |  |  |  | 600,000 | $ 1,200,000 | 1,100,000 |  |  |  |
Unrecognized compensation expenses |  |  |  |  | $ 1,500,000 |  |  |  |  |  |
Weighted average period over which options will be recognized |  |  |  |  | 1 year 2 months 12 days |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  |  |  |  | 3 year |  |  |  |  |  |
Common shares issued for share based compensation | shares |  |  |  | 156,415 |  |  |  |  |  |  |
Dividends Payable, Amount Per Share | $ / shares |  |  |  |  |  |  |  | $ 0.15 |  |  |
Restricted Performance Share Units Plan [Member] | Executive Officer [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number | shares |  |  |  |  | 533,128 | 364,267 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares |  |  |  |  | 231,388 |  |  |  |  |  |
Aggregate share-based awards awarded to executives | shares |  |  | 231,388 |  |  |  |  |  | 186,395 | 61,720 | 134,284
Restricted Performance Share Units Plan [Member] | Cliff Vest [Member] | Executive Officer [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights |  |  |  |  | three year cliff vesting period |  |  |  |  |  |
Employee Share Purchase Plan [Member] |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Share-based compensation expense |  |  |  |  | $ 200,000 | $ 100,000 | 100,000 |  |  |  |
Share purchases made by employees under ESPP |  |  |  |  | 85% of the average closing price per share for a specified period |  |  |  |  |  |
Maximum participant contribution, percentage of compensation |  |  |  |  | 20.00% |  |  |  |  |  |
Maximum participant contribution, dollar amount |  |  |  |  | $ 50,000 |  |  |  |  |  |
Aggregate share-based awards awarded to executives | shares |  |  |  |  | 1,250,000 |  |  |  |  |  |
Stock Issued During Period, Value, Employee Stock Purchase Plan |  |  |  |  | $ 400,000 | $ 500,000 | $ 400,000 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Purchase Date |  |  |  |  | 15.00% |  |  |  |  |  |

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