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v3.19.3.a.u2

Notes Payable - Additional Information (Detail) - USD ($) |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Nov. 05, 2015 | Mar. 17, 2014 | Dec. 31, 2019 | Dec. 31, 2018 | Mar. 31, 2016
Debt Instrument [Line Items] |  |  |  |  |
Consolidated Fixed Charge Coverage Ratio |  |  | 2.50% |  |
Consolidated Fixed Charge Coverage Ratio, actual |  |  | 4.27% |  |
Consolidated Leverage Ratio |  |  | 275.00% |  |
Consolidated Leverage Ratio, actual |  |  | 124.00% |  |
Line of credit facility covenants tangible net worth description |  |  | Permit Tangible Net Worth, calculated as of the last day of each fiscal quarter, to be less than the sum of (i) $229.0 million, plus (ii) 25% of net income for such fiscal quarter subsequent to December 31, 2010, plus (iii) 90% of the net cash proceeds from the issuance of the Company’s capital stock after December 31, 2010. |  |
Tangible Net Worth sum |  |  | $ 388,100,000 |  |
Consolidated Net Income |  |  | 25.00% |  |
Percentage of net cash proceeds from issuance of capital stock |  |  | 90.00% |  |
Actual tangible net worth |  |  | $ 598,500,000 |  |
Senior notes principal balance outstanding |  |  | $ 293,459,000 | $ 298,603,000 |
Series B Senior Notes [Member] | 3.68% Series B senior notes due in 2021 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Proceeds from issuance of senior notes |  | $ 40,000,000.0 |  |  |
Senior notes interest rate |  | 3.68% | 3.68% |  |
Debt instrument, maturity date |  |  | Mar. 17, 2021 |  |
Senior notes description |  |  | The Series B Senior Notes are an unsecured obligation of the Company, bear interest at a rate of 3.68% per annum and mature on March 17, 2021. Interest on the Series B Senior Notes is payable semi-annually beginning on September 17, 2014 and continuing thereafter on March 17 and September 17 of each year until maturity. |  |
Senior notes interest payment |  |  | Semi-annually |  |
Senior notes principal balance outstanding |  |  | $ 40,000,000 | 40,000,000 |
Series C Senior Notes [Member] | 3.84% Series C senior notes due in 2022 [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Proceeds from issuance of senior notes | $ 60,000,000.0 |  |  |  |
Senior notes interest rate | 3.84% |  | 3.84% |  |
Debt instrument, maturity date |  |  | Nov. 05, 2022 |  |
Senior notes description |  |  | November 5, 2022. Interest on the Series C Senior Notes is payable semi-annually beginning on May 5, 2016 and continuing thereafter on November 5 and May 5 of each year until maturity. |  |
Senior notes interest payment |  |  | semi-annually |  |
Senior notes principal balance outstanding |  |  | $ 60,000,000 | $ 60,000,000 |
Debt instrument, date of first required payment |  |  | May 05, 2016 |  |
Minimum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Credit facility, maximum |  |  |  |  | $ 10,000,000.0
Tangible Net Worth sum |  |  | $ 229,000,000.0 |  |
Maximum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Credit facility, maximum |  |  |  |  | $ 12,000,000.0
Credit Facility [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Revolving credit facility, maturity period |  |  | 5 years |  |
Revolving credit facility, maturity date |  |  | Mar. 31, 2021 |  |
Credit facility, maximum |  |  | $ 420,000,000.0 |  |
Revolving credit facility, available maximum borrowing capacity |  |  | 620,000,000.0 |  |
Additional commitments |  |  | $ 200,000,000.0 |  |
Consolidated Fixed Charge Coverage Ratio |  |  | 2.50% |  |
Consolidated Fixed Charge Coverage Ratio, actual |  |  | 4.27% |  |
Consolidated Leverage Ratio |  |  | 275.00% |  |
Consolidated Leverage Ratio, actual |  |  | 124.00% |  |
Line of credit facility covenants tangible net worth description |  |  | Permit Tangible Net Worth as of the end of any fiscal quarter of the Company to be less than the sum of (i) $246.1 million plus (ii) 25% of the Company’s Consolidated Net Income (as defined in the Amended Credit Facility) (but only if a positive number) for each fiscal quarter ended subsequent to December 31, 2011 |  |
Tangible Net Worth sum |  |  | $ 388,100,000 |  |
Consolidated Net Income |  |  | 25.00% |  |
Percentage of net cash proceeds from issuance of capital stock |  |  | 90.00% |  |
Actual tangible net worth |  |  | $ 598,500,000 |  |
Debt instrument description of variable rate basis |  |  | (i) LIBOR plus a defined margin, or (ii) the Agent bank’s prime rate (“base rate”) plus a margin. The applicable margin for each type of loan is measured based upon the Consolidated Leverage Ratio at the end of the prior fiscal quarter and ranges from 1.00% to 1.75% for LIBOR loans and 0% to 0.75% for base rate loans. In addition, the Company pays an unused commitment fee for the portion of the $420.0 million credit facility that is not used. These fees are based upon the Consolidated Leverage Ratio and range from 0.15% to 0.30%. As of December 31, 2019 and 2018, the applicable margins were 1.25% for LIBOR based loans, 0.25% for base rate loans and 0.20% for unused fees. Amounts borrowed under the Sweep Service Facility are based upon the MUFG Union Bank, N.A. base rate plus an applicable margin and an unused commitment fee for the portion of the $12.0 million facility not used. |  |
Unused commitment fees |  |  | $ 420,000,000.0 |  |
Credit Facility [Member] | Unused Fees [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument interest rate at period end |  |  | 0.20% | 0.20% |
Credit Facility [Member] | LIBOR Loans [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument interest rate at period end |  |  | 1.25% | 1.25% |
Credit Facility [Member] | Base Rate Loans [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument interest rate at period end |  |  | 0.25% | 0.25% |
Credit Facility [Member] | Sweep Service Facility [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Credit facility, maximum |  |  | $ 432,000,000.0 |  |
Revolving credit facility, available maximum borrowing capacity |  |  | 238,500,000 |  |
Amount outstanding |  |  | 193,500,000 |  |
Unused commitment fees |  |  | 12,000,000.0 |  |
Credit Facility [Member] | Minimum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Tangible Net Worth sum |  |  | $ 246,100 |  |
Leverage ratio |  |  | 0.15% |  |
Credit Facility [Member] | Minimum [Member] | LIBOR Loans [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Leverage ratio |  |  | 1.00% |  |
Credit Facility [Member] | Minimum [Member] | Base Rate Loans [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Leverage ratio |  |  | 0.00% |  |
Credit Facility [Member] | Maximum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Leverage ratio |  |  | 0.30% |  |
Credit Facility [Member] | Maximum [Member] | LIBOR Loans [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Leverage ratio |  |  | 1.75% |  |
Credit Facility [Member] | Maximum [Member] | Base Rate Loans [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Leverage ratio |  |  | 0.75% |  |
Unsecured revolving credit facility before Renewal [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Credit facility, maximum |  |  | $ 420,000,000.0 |  |
Letters of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Credit facility, maximum |  |  | 25,000,000.0 |  |
Swingline Loans [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Credit facility, maximum |  |  | $ 10,000,000.0 |  |

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