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v3.19.1

Debt - Narrative (Details) $ in Millions |  | 3 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2016 USD ($) | Mar. 31, 2019 USD ($) equipment-note | Dec. 31, 2018 USD ($) | Sep. 28, 2018 USD ($)
Secured Debt [Member] | Credit Agreement [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Option to increase borrowing capacity | $ 100.0 |  |  |
Maximum borrowing capacity | $ 250.0 |  |  |
Interest coverage ratio |  | 3.0 |  |
Percentage of capital stock from direct foreign subsidiaries | 65.00% |  |  |
Maximum acquisition consideration under credit agreement |  | $ 50.0 |  |
Deferred debt issuance costs |  | $ 0.6 |  |
Debt instrument covenant leveraged debt ratio restriction |  | 2.25 |  |
Leverage coverage ratio expansion |  | 3.5 |  |
Leverage coverage ratio |  | 3.0 |  |
Debt instrument term | 5 years |  |  |
Interest rate on borrowings outstanding |  | 3.51% |  |
Secured Debt [Member] | Credit Agreement [Member] | Canada, Dollars [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maximum borrowing capacity | $ 50.0 |  |  |
Secured Debt [Member] | Credit Agreement [Member] | Letter of Credit [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maximum borrowing capacity |  |  |  | $ 150.0
Letters of credit outstanding |  | $ 21.2 | $ 21.2 |
Secured Debt [Member] | Credit Agreement [Member] | Letter of Credit [Member] | Insurance Program Obligations [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Letters of credit outstanding |  | 17.6 | 17.6 |
Secured Debt [Member] | Credit Agreement [Member] | Letter of Credit [Member] | Contract Performance Obligations [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Letters of credit outstanding |  | $ 3.6 | $ 3.6 |
Secured Debt [Member] | Credit Agreement [Member] | Maximum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Commitment fee on unused capacity |  | 0.375% |  |
Secured Debt [Member] | Credit Agreement [Member] | Maximum [Member] | Performance letters of credit [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Letter of credit facility commitment percentage |  | 1.125% |  |
Secured Debt [Member] | Credit Agreement [Member] | Maximum [Member] | Non-performance Letters Of Credit [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Letter of credit facility commitment percentage |  | 2.125% |  |
Secured Debt [Member] | Credit Agreement [Member] | Maximum [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate margin |  | 2.00% |  |
Secured Debt [Member] | Credit Agreement [Member] | Maximum [Member] | Base Rate [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate margin |  | 1.00% |  |
Secured Debt [Member] | Credit Agreement [Member] | Minimum [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Commitment fee on unused capacity |  | 0.20% |  |
Secured Debt [Member] | Credit Agreement [Member] | Minimum [Member] | Performance letters of credit [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Letter of credit facility commitment percentage |  | 0.625% |  |
Secured Debt [Member] | Credit Agreement [Member] | Minimum [Member] | Non-performance Letters Of Credit [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Letter of credit facility commitment percentage |  | 1.125% |  |
Secured Debt [Member] | Credit Agreement [Member] | Minimum [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate margin |  | 1.00% |  |
Secured Debt [Member] | Credit Agreement [Member] | Minimum [Member] | Base Rate [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate margin |  | 0.00% |  |
Notes Payable to Banks [Member] | Master Loan Agreement [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Number of equipment notes (equipment note) | equipment-note |  | 5 |  |

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