XML 44 R31.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Debt - Additional Information (Detail) - USD ($) |  |  | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Mar. 23, 2018 | Jun. 02, 2015 | Jun. 30, 2018 | Dec. 31, 2017
Credit and Loan Agreement [Line Items] |  |  |  |
Credit agreement initiation date |  | Jun. 02, 2015 |  |
Senior unsecured revolving credit agreement |  | $ 225,000,000 |  |
Term loan under credit agreement |  | $ 50,000,000 |  |
Revolving facility optional extension period |  | 1 year |  |
Third Restated Prudential Note Purchase Agreement [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Senior unsecured note, issuance date |  |  | Jun. 21, 2018 |
Amount of rate increase in case of default |  |  | 2.00% |
Third Restated Prudential Note Purchase Agreement [Member] | Series A Note [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Feb. 25, 2021 |
Interest rate on agreement |  |  | 6.00% |
Senior unsecured note, aggregate amount issued |  |  | $ 100,000,000 |
Third Restated Prudential Note Purchase Agreement [Member] | Series B Notes [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Jun. 02, 2023 |
Interest rate on agreement |  |  | 5.35% |
Senior unsecured note, aggregate amount issued |  |  | $ 75,000,000 |
Third Restated Prudential Note Purchase Agreement [Member] | Series C Notes [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Feb. 25, 2025 |
Interest rate on agreement |  |  | 4.75% |
Senior unsecured note, aggregate amount issued |  |  | $ 50,000,000 |
Third Restated Prudential Note Purchase Agreement [Member] | Series D Notes [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Jun. 21, 2028 |
Interest rate on agreement |  |  | 5.47% |
Senior unsecured note, aggregate amount issued |  |  | $ 50,000,000 |
Third Restated Prudential Note Purchase Agreement [Member] | Series E Notes [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Jun. 21, 2028 |
Interest rate on agreement |  |  | 5.47% |
Senior unsecured note, aggregate amount issued |  |  | $ 50,000,000 |
Revolving Facility [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Revolving facility under credit agreement |  | $ 175,000,000 |  |
Credit facility amount | $ 250,000,000 |  |  |
Revolving facility optional extension period |  |  | 1 year |
Credit facility agreement, optional extended maturity date |  |  | Mar. 31, 2023 |
Credit agreement maturity date | Jun. 30, 2018 |  |  |
Credit agreement extended maturity date | Mar. 23, 2022 |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Mar. 23, 2022 | Mar. 23, 2022
Interest rate on agreement |  |  | 3.53% | 3.53%
Revolving Facility [Member] | Maximum [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Option to increase credit facility |  |  | $ 300,000,000 |
Annual commitment fee on undrawn funds |  |  | 0.25% |
Revolving Facility [Member] | Maximum [Member] | Base Rate [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 1.30% |
Revolving Facility [Member] | Maximum [Member] | LIBOR [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 2.30% |
Revolving Facility [Member] | Minimum [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Annual commitment fee on undrawn funds |  |  | 0.15% |
Revolving Facility [Member] | Minimum [Member] | Base Rate [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 0.50% |
Revolving Facility [Member] | Minimum [Member] | LIBOR [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 1.50% |
Term Loan [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Credit facility amount |  |  | $ 600,000,000 |
Credit agreement maturity date | Jun. 30, 2020 |  |  |
Credit agreement extended maturity date | Mar. 23, 2023 |  |  |
Senior unsecured note purchase agreement, maturity date |  |  | Mar. 23, 2023 | Mar. 23, 2023
Interest rate on agreement |  |  | 3.54% | 3.54%
Term Loan [Member] | Maximum [Member] | Base Rate [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 1.25% |
Term Loan [Member] | Maximum [Member] | LIBOR [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 2.25% |
Term Loan [Member] | Minimum [Member] | Base Rate [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 0.45% |
Term Loan [Member] | Minimum [Member] | LIBOR [Member] |  |  |  |
Credit and Loan Agreement [Line Items] |  |  |  |
Credit agreement margin on borrowing base rate |  |  | 1.45% |

X
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- Definition The increase in basis points to the base interest rate in the event of a default on the credit agreement. + References No definition available. + Details
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- Definition Line of credit facility agreement maturity date. + References No definition available. + Details
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- Definition Line of credit facility extended maturity date. + References No definition available. + Details
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- Definition Line of credit facility optional extended maturity date. + References No definition available. + Details
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- Definition The length of time the Revolving Facility may be extended. + References No definition available. + Details
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- Definition The stated amount of the senior unsecured credit agreement which does not include the amount by which the credit facility can be increased. + References No definition available. + Details
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- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Date the debt instrument was issued, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(2)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Date the credit facility first became available, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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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. + References No definition available. + Details
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- Definition Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)(a)(2)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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