Line of Credit and Short-Term Borrowings - Additional Information (Detail) - Line of Credit [Member] - USD ($) |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Jun. 30, 2015 |
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| Debt Instrument [Line Items] | |||
| Maximum amount of credit facility | $ 250,000,000 | ||
| Maturity date of credit agreement | Jun. 30, 2020 | ||
| Line of credit facility, interest rate | Borrowings bear interest at the Company’s election based on (a) LIBOR or (b) the greater of (i) the Prime Rate, (ii) the Federal Funds Rate plus 0.5% and (iii) LIBOR for a 30-day period plus 1.0%, in each case, plus an applicable margin based on the average daily principal balance of revolving loans available under the Credit Agreement. | ||
| Unused line of credit fee | 0.25% | ||
| Line of credit facility, expiration period | 5 years | ||
| Line of credit facility, outstanding amount | $ 100,000 | $ 100,000 | |
| Other Assets [Member] | |||
| Debt Instrument [Line Items] | |||
| Debt closing and arrangement fees | $ 1,100,000 | ||
| Federal Funds Rate [Member] | |||
| Debt Instrument [Line Items] | |||
| Interest rate of line of credit agreement | 0.50% | ||
| LIBOR Loans [Member] | |||
| Debt Instrument [Line Items] | |||
| Interest rate of line of credit agreement | 1.00% | ||
| Maximum [Member] | |||
| Debt Instrument [Line Items] | |||
| Line of credit, increase | $ 100,000,000 |
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- Definition That amount that the line of credit is subject to increase. No definition available.
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- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. No definition available.
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- Definition Amount of the fee that accompanies borrowing money under the debt instrument. 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 Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. No definition available.
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Date the credit facility terminates, in CCYY-MM-DD format. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility. No definition available.
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