Nature of Operations and Summary of Significant Accounting Policies - Summary of Available-for-sale Investments (Details) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Debt Instrument [Line Items] | ||
| Adjusted Cost | $ 73,470 | $ 57,486 |
| Gross Unrealized Gains/Losses | (2) | (3) |
| Fair Value | 73,468 | 57,483 |
| Municipal bonds and notes | ||
| Debt Instrument [Line Items] | ||
| Adjusted Cost | 43,490 | 35,222 |
| Gross Unrealized Gains/Losses | 0 | 2 |
| Fair Value | 43,490 | 35,224 |
| Corporate debt securities | ||
| Debt Instrument [Line Items] | ||
| Adjusted Cost | 1,673 | 5,029 |
| Gross Unrealized Gains/Losses | (2) | (5) |
| Fair Value | 1,671 | 5,024 |
| Financial institution instruments | ||
| Debt Instrument [Line Items] | ||
| Adjusted Cost | 28,307 | 17,235 |
| Gross Unrealized Gains/Losses | 0 | 0 |
| Fair Value | $ 28,307 | $ 17,235 |
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. No definition available.
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. 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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