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Borrowings - Long Term Borrowings (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Line of Credit Facility [Line Items] |  |
Long-term borrowings | $ 4,354,037 | $ 4,284,304
Weighted Average Interest Rate | 3.07% | 3.27%
Average Balance | $ 4,483,858 | $ 3,893,533
Floating-rate borrowings |  |
Line of Credit Facility [Line Items] |  |
Long-term borrowings | $ 1,525,976 | $ 1,802,609
Weighted Average Interest Rate | 2.61% | 3.26%
Average Balance | $ 1,731,675 | $ 1,720,540
Fixed-rate borrowings |  |
Line of Credit Facility [Line Items] |  |
Long-term borrowings | $ 2,828,061 | $ 2,481,695
Weighted Average Interest Rate | 3.31% | 3.28%
Average Balance | $ 2,752,183 | $ 2,172,993

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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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