Commitments and Contingent Liabilities - Maximum Potential Total of Future Payments Under Commitment Instruments (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	$ 289,249
Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	184,161
Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	105,088
Less Than 1  Year
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	286,161
Less Than 1  Year | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	184,161
Less Than 1  Year | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	102,000
1-3 Years
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	3,088
1-3 Years | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
1-3 Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	3,088
3-5 Years
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
3-5 Years | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
3-5 Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Beyond 5  Years
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Beyond 5  Years | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Beyond 5  Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Firm Transportation | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	181,194
Firm Transportation | Less Than 1  Year | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	181,194
Firm Transportation | 1-3 Years | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Firm Transportation | 3-5 Years | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Firm Transportation | Beyond 5  Years | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Other | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	2,967
Other | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	8,834
Other | Less Than 1  Year | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	2,967
Other | Less Than 1  Year | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	7,206
Other | 1-3 Years | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Other | 1-3 Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	1,628
Other | 3-5 Years | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Other | 3-5 Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Other | Beyond 5  Years | Letters of Credit
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Other | Beyond 5  Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Employee-Related | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	2,600
Employee-Related | Less Than 1  Year | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	2,600
Employee-Related | 1-3 Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Employee-Related | 3-5 Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Employee-Related | Beyond 5  Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Environmental | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	11,984
Environmental | Less Than 1  Year | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	10,524
Environmental | 1-3 Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	1,460
Environmental | 3-5 Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Environmental | Beyond 5  Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Financial Guarantees | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	81,670
Financial Guarantees | Less Than 1  Year | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	81,670
Financial Guarantees | 1-3 Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Financial Guarantees | 3-5 Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	0
Financial Guarantees | Beyond 5  Years | Surety Bonds
Loss Contingencies [Line Items]
Maximum potential total of future payments under commitments	$ 0