XML 84 R70.htm IDEA: XBRL DOCUMENT v3.10.0.1
Credit Agreement - Schedule of Credit Agreements (Parenthetical) (Detail) - Credit Agreement [Member] - USD ($)
Dec. 31, 2018
Dec. 31, 2017
Line Of Credit Facility [Line Items]    
Outstanding letters of credit [1],[2] $ 2,218,000 $ 5,070,000 [3]
BMO Harris Bank N.A. ("BMO Harris") [Member]    
Line Of Credit Facility [Line Items]    
Outstanding letters of credit 300,000 800,000
BMO Harris Bank N.A. ("BMO Harris") [Member] | Letter of Credit [Member]    
Line Of Credit Facility [Line Items]    
Letters of credit, sublimit and aggregate commitments 50,000,000 95,000,000
BMO Harris Bank N.A. ("BMO Harris") [Member] | Letter of Credit Sublimit [Member]    
Line Of Credit Facility [Line Items]    
Letters of credit, sublimit and aggregate commitments $ 25,000,000 $ 60,000,000
[1] As of December 31, 2017, $5.1 million of restricted short-term investments provided collateral for our letters of credit.
[2] As of December 31, 2018 and 2017, outstanding letters of credit not related to the credit agreements totaled $0.3 million and $0.8 million, respectively, which amounts are fully collateralized with restricted cash, which is in addition to the $5.1 million referenced in this Note 11 as of December 31, 2017.
[3] Amounts listed as of and for the year ended December 31, 2017 relate to our previous credit agreement.