LONG-TERM DEBT AND LINES OF CREDIT - Summary (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Other borrowings	$ 34,266	$ 0
Total long-term debt	9,021,077	5,130,243
Less current portion	33,373	115,075
Long-term debt, excluding current portion	8,987,704	5,015,168
Unsecured term loan facility
Debt Instrument [Line Items]
Gross long-term debt	1,980,886	0
Unsecured revolving credit facility
Debt Instrument [Line Items]
Gross long-term debt	783,000	0
Secured term loans (outstanding under our Prior Credit Facility)
Debt Instrument [Line Items]
Gross long-term debt	0	4,426,243
Secured revolving credit facility (outstanding under our Prior Credit Facility)
Debt Instrument [Line Items]
Gross long-term debt	0	704,000
Other borrowings
Debt Instrument [Line Items]
Gross long-term debt	40,374	0
3.800% senior notes due April 1, 2021 \| Senior Notes
Debt Instrument [Line Items]
Gross long-term debt	$ 763,194	0
Stated interest rate (as a percent)	3.80%
3.750% senior notes due June 1, 2023 \| Senior Notes
Debt Instrument [Line Items]
Gross long-term debt	$ 568,598	0
Stated interest rate (as a percent)	3.75%
4.000% senior notes due June 1, 2023 \| Senior Notes
Debt Instrument [Line Items]
Gross long-term debt	$ 574,170	0
Stated interest rate (as a percent)	4.00%
2.650% senior notes due February 15, 2025 \| Senior Notes
Debt Instrument [Line Items]
Gross long-term debt	$ 991,090	0
Stated interest rate (as a percent)	2.65%
4.800% senior notes due April 1, 2026 \| Senior Notes
Debt Instrument [Line Items]
Gross long-term debt	$ 823,448	0
Stated interest rate (as a percent)	4.80%
4.450% senior notes due June 1, 2028 \| Senior Notes
Debt Instrument [Line Items]
Gross long-term debt	$ 488,081	0
Stated interest rate (as a percent)	4.45%
3.200% senior notes due August 15, 2029 \| Senior Notes
Debt Instrument [Line Items]
Gross long-term debt	$ 1,234,560	0
Stated interest rate (as a percent)	3.20%
4.150% senior notes due August 15, 2049 \| Senior Notes
Debt Instrument [Line Items]
Gross long-term debt	$ 739,410	$ 0
Stated interest rate (as a percent)	4.15%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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