Long-Term Debt - Term Loan (Details)  | 
 Mar. 31, 2016  
USD ($) 
 | 
 Dec. 31, 2015  
USD ($) 
 | 
 Oct. 31, 2012  
USD ($)  
bank 
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|---|---|---|---|
| Debt Instrument [Line Items] | |||
| Number of banks | bank | 2 | ||
| Term Loan | |||
| Debt Instrument [Line Items] | |||
| Weighted average interest rate | 2.63% | ||
| Term Loan | Variable Rate Construction Term Loan | |||
| Debt Instrument [Line Items] | |||
| Original principal amount | $ 47,234,000 | ||
| Debt outstanding | $ 37,814,000 | ||
| Weighted average interest rate | 3.63% | ||
| Term Loan | 2015 Variable Rate Construction Term Loan | |||
| Debt Instrument [Line Items] | |||
| Original principal amount | $ 20,746,000 | ||
| Debt outstanding | $ 17,663,000 | ||
| Term Loan | 2015 Variable Rate Term Loan | |||
| Debt Instrument [Line Items] | |||
| Debt outstanding | $ 20,746,000 | ||
| Weighted average interest rate | 3.14% | 
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- Definition Variable-Rate Construction and Term Loans, Number of Banks No definition available. 
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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition Weighted average interest rate of debt outstanding. No definition available. 
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