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CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2018 | Sep. 30, 2017
Cash Flows from Operating Activities: |  |
Net income (loss) | $ 20,096 | $ (41,820)
Adjustments to reconcile net income (loss) to cash provided by operating activities |  |
Depreciation and amortization | 51,572 | 46,307
Depletion of landfill operating lease obligations | 7,827 | 6,834
Interest accretion on landfill and environmental remediation liabilities | 4,291 | 3,205
Amortization of debt issuance costs and discount on long-term debt | 1,875 | 2,005
Stock-based compensation | 6,366 | 4,784
Gain on sale of property and equipment | (414) | (43)
Southbridge Landfill non-cash closure charge | 1,354 | 63,526
Southbridge Landfill insurance recovery for investing activities | (3,506) | 0
Development project charge | 311 | 0
Non-cash expense from acquisition activities and other items | 211 | 0
Loss on debt extinguishment | 7,352 | 517
Deferred income taxes | 79 | 384
Changes in assets and liabilities, net of effects of acquisitions and divestitures: |  |
Accounts receivable | (12,161) | (3,887)
Accounts payable | 8,009 | 2,046
Prepaid expenses, inventories and other assets | 829 | (1,722)
Accrued expenses, contract liabilities and other liabilities | (4,174) | (3,036)
Net cash provided by operating activities | 89,917 | 79,100
Cash Flows from Investing Activities: |  |
Acquisitions, net of cash acquired | (58,176) | (3,563)
Additions to property, plant and equipment | (51,841) | (43,412)
Payments on landfill operating lease contracts | (5,006) | (3,731)
Proceeds from sale of property and equipment | 609 | 657
Proceeds from property insurance settlement | 992 |
Net cash used in investing activities | (109,916) | (50,049)
Cash Flows from Financing Activities: |  |
Proceeds from long-term borrowings | 566,800 | 146,400
Principal payments on long-term debt | (540,611) | (175,244)
Payments of debt issuance costs | (5,573) | (1,451)
Proceeds from the exercise of share based awards | 471 | 1,003
Net cash provided by (used in) financing activities | 21,087 | (29,292)
Net increase (decrease) in cash and cash equivalents | 1,088 | (241)
Cash and cash equivalents, beginning of period | 1,995 | 2,544
Cash and cash equivalents, end of period | 3,083 | 2,303
Cash paid during the period for: |  |
Interest | 16,950 | 19,417
Income taxes, net of refunds | 84 | 248
Supplemental Disclosure of Non-Cash Investing and Financing Activities: |  |
Non-current assets obtained through long-term obligations | 4,342 | 3,564
Contingent consideration from business combinations | 2,924 | 0
Southbridge Landfill |  |
Adjustments to reconcile net income (loss) to cash provided by operating activities |  |
Development project charge | 0 | 9,149
Cash Flows from Investing Activities: |  |
Proceeds from property insurance settlement | $ 3,506 | $ 0

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- Definition The non-cash portion of the aggregate charge associated with the closure of a landfill, which includes a non-cash asset impairment charge, a non-cash project development charge, a reserve for a legal settlement and a non-cash environmental remediation charge. + References No definition available. + 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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