USE OF DERIVATIVES, OFFSETTING DISCLOSURES AND CHANGES IN OTHER COMPREHENSIVE INCOME BY COMPONENT - Schedule of Swap Agreements Expiration Period and Characteristics (Details) $ in Thousands	Mar. 31, 2018 USD ($)
Notional Disclosures [Abstract]
Notional Amount	$ 6,850,000
Interest Rate SWAP Currently-Paying Contracts Expiring Second Quarter 2018 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 600,000
Average Fixed-Rate Payment Requirement	0.79%
Interest Rate SWAP Currently-Paying Contracts Expiring Third Quarter 2018 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 400,000
Average Fixed-Rate Payment Requirement	0.88%
Interest Rate SWAP Currently-Paying Contracts Expiring Fourth Quarter 2018 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 800,000
Average Fixed-Rate Payment Requirement	1.15%
Interest Rate SWAP Currently-Paying Contracts Expiring First Quarter 2019 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 950,000
Average Fixed-Rate Payment Requirement	1.58%
Interest Rate SWAP Currently-Paying Contracts Expiring Second Quarter 2019 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 1,650,000
Average Fixed-Rate Payment Requirement	1.33%
Interest Rate SWAP Currently-Paying Contracts Expiring Third Quarter 2019 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 550,000
Average Fixed-Rate Payment Requirement	1.40%
Interest Rate SWAP Currently-Paying Contracts Expiring Fourth Quarter 2019 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 700,000
Average Fixed-Rate Payment Requirement	1.72%
Interest Rate SWAP Currently-Paying Contracts Expiring First Quarter 2020 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 600,000
Average Fixed-Rate Payment Requirement	2.07%
Interest Rate SWAP Currently-Paying Contracts Expiring Second Quarter 2020 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 100,000
Average Fixed-Rate Payment Requirement	2.56%
Interest Rate SWAP Currently-Paying Contracts Expiring Third Quarter 2020 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 200,000
Average Fixed-Rate Payment Requirement	1.64%
Interest Rate SWAP Currently-Paying Contracts Expiring Fourth Quarter 2020 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 200,000
Average Fixed-Rate Payment Requirement	2.04%
Interest Rate SWAP Currently-Paying Contracts Expiring First Quarter 2021 [Member]
Notional Disclosures [Abstract]
Notional Amount	$ 100,000
Average Fixed-Rate Payment Requirement	2.67%