COMMITMENTS AND CONTINGENT LIABILITIES - Schedule of Commitment Expiration (Details) $ in Thousands	Jun. 30, 2019 USD ($)
Guarantor Obligations [Line Items]
Total Amounts Committed	$ 741,596
Less Than 1 Year	703,588
1-3 Years	37,129
3-5 Years	398
Beyond 5 Years	481
Letters of Credit
Guarantor Obligations [Line Items]
Total Amounts Committed	96,101
Less Than 1 Year	74,378
1-3 Years	21,723
3-5 Years	0
Beyond 5 Years	0
Letters of Credit | Employee-Related
Guarantor Obligations [Line Items]
Total Amounts Committed	65,292
Less Than 1 Year	46,623
1-3 Years	18,669
3-5 Years	0
Beyond 5 Years	0
Letters of Credit | Environmental
Guarantor Obligations [Line Items]
Total Amounts Committed	398
Less Than 1 Year	398
1-3 Years	0
3-5 Years	0
Beyond 5 Years	0
Letters of Credit | Other
Guarantor Obligations [Line Items]
Total Amounts Committed	30,411
Less Than 1 Year	27,357
1-3 Years	3,054
3-5 Years	0
Beyond 5 Years	0
Surety Bonds
Guarantor Obligations [Line Items]
Total Amounts Committed	625,727
Less Than 1 Year	621,546
1-3 Years	4,181
3-5 Years	0
Beyond 5 Years	0
Surety Bonds | Employee-Related
Guarantor Obligations [Line Items]
Total Amounts Committed	90,033
Less Than 1 Year	90,033
1-3 Years	0
3-5 Years	0
Beyond 5 Years	0
Surety Bonds | Environmental
Guarantor Obligations [Line Items]
Total Amounts Committed	531,959
Less Than 1 Year	528,265
1-3 Years	3,694
3-5 Years	0
Beyond 5 Years	0
Surety Bonds | Other
Guarantor Obligations [Line Items]
Total Amounts Committed	3,735
Less Than 1 Year	3,248
1-3 Years	487
3-5 Years	0
Beyond 5 Years	0
Guarantees
Guarantor Obligations [Line Items]
Total Amounts Committed	19,768
Less Than 1 Year	7,664
1-3 Years	11,225
3-5 Years	398
Beyond 5 Years	481
Guarantees | Other
Guarantor Obligations [Line Items]
Total Amounts Committed	19,768
Less Than 1 Year	7,664
1-3 Years	11,225
3-5 Years	398
Beyond 5 Years	$ 481