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CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Cash Flows from Operating Activities: |  |  |
Net income (loss) | $ 6,420 | $ (21,799) | $ (6,858)
net income (loss) to net cash provided by operating activities: |  |  |
Depreciation and amortization | 70,508 | 62,102 | 61,856
Depletion of landfill operating lease obligations | 9,724 | 9,646 | 9,295
Interest accretion on landfill and environmental remediation liabilities | 5,708 | 4,482 | 3,606
Amortization of debt issuance costs and discounts on long-term debt | 2,449 | 2,692 | 3,881
Stock-based compensation | 8,445 | 6,432 | 3,393
Environmental remediation charge | 0 | 0 | 900
(Gain) loss on sale of property and equipment | (492) | 49 | (574)
Southbridge Landfill non-cash closure charge | 16,179 | 63,526 | 0
Southbridge Landfill insurance recovery for investing activities | (3,506) | 0 | 0
Non-cash expense from acquisition activities and other items | 757 | 0 | 0
Development project charge | 311 | 0 | 0
Loss on debt extinguishment | 7,352 | 517 | 13,747
Impairment of investments | 1,069 | 0 | 0
Deferred income taxes | 1,250 | (15,525) | 583
Changes in assets and liabilities, net of effects of acquisitions and divestitures: |  |  |
Accounts receivable | (5,833) | (4,664) | (1,029)
Accounts payable | 9,091 | 2,084 | 76
Prepaid expenses, inventories and other assets | 535 | (1,404) | (2,256)
Accrued expenses and other liabilities | (9,133) | (600) | (6,186)
Net cash provided by operating activities | 120,834 | 107,538 | 80,434
Cash Flows from Investing Activities: |  |  |
Acquisitions, net of cash acquired | (88,918) | (5,056) | (2,839)
Additions to property, plant and equipment | (73,232) | (64,862) | (54,238)
Payments on landfill operating lease contracts | (7,415) | (7,240) | (7,249)
Proceeds from property insurance settlement | 992 | 0 | 0
Proceeds from sale of property and equipment | 870 | 711 | 1,362
Net cash used in investing activities | (164,197) | (76,447) | (62,964)
Cash Flows from Financing Activities: |  |  |
Proceeds from long-term borrowings | 634,700 | 185,500 | 604,850
Principal payments on long-term debt | (584,223) | (216,966) | (608,198)
Payments of debt issuance costs | (5,573) | (1,452) | (8,146)
Payments of debt extinguishment costs | 0 | 0 | (7,219)
Proceeds from the exercise of share based awards | 471 | 1,278 | 128
Net cash provided by (used in) financing activities | 45,375 | (31,640) | (18,585)
Net increase (decrease) in cash, cash equivalents and restricted cash | 2,012 | (549) | (1,115)
Cash, cash equivalents and restricted cash, beginning of period | 1,995 | 2,544 | 3,659
Cash, cash equivalents and restricted cash, end of period | 4,007 | 1,995 | 2,544
Supplemental Disclosures of Cash Flow Information: |  |  |
Interest | 23,523 | 25,029 | 42,712
Income taxes, net of refunds | 105 | 146 | 274
Supplemental Disclosures of Non-Cash Investing and Financing Activities: |  |  |
Non-current assets acquired through long-term obligations | 7,092 | 3,564 | $ 2,299
Southbridge Landfill |  |  |
net income (loss) to net cash provided by operating activities: |  |  |
Southbridge Landfill non-cash closure charge | 6,012 | 0 |
Development project charge | 0 | $ 9,149 |
Cash Flows from Investing Activities: |  |  |
Proceeds from property insurance settlement | $ 3,506 |  |

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- Definition Amount of cash inflow for proceeds from settlement of insurance claim, classified as investing activities. Excludes insurance settlement classified as operating activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 21B -URI http://asc.fasb.org/extlink&oid=98514028&loc=SL94080549-108585 + Details
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- Definition The cash inflow associated with security instrument that either represents a creditor or an ownership relationship with the holder of the investment security with a maturity of beyond one year or normal operating cycle, if longer. Includes proceeds from (a) debt, (b) capital lease obligations, (c) mandatory redeemable capital securities, and (d) any combination of (a), (b), or (c). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 + Details
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- Definition Amount of cash inflow from issuance of shares under share-based compensation arrangement. Issuance includes, but is not limited to, exercise of stock options and similar instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901 + Details
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- Definition The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585 + Details
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- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4K -URI http://asc.fasb.org/extlink&oid=84234705&loc=SL4591552-111686 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4569616-111683 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84161450&loc=SL4573702-111684 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4J -URI http://asc.fasb.org/extlink&oid=84234705&loc=SL4591551-111686 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=84161450&loc=SL4573702-111684 + Details
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- Definition The cash outflow associated with security instruments that either represent a creditor or an ownership relationship with the holder of the investment security with a maturity of beyond one year or normal operating cycle, if longer. Includes repayments of (a) debt, (b) capital lease obligations, (c) mandatory redeemable capital securities, and (d) any combination of (a), (b), or (c). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585 + Details
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- Definition The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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