A summary of long-term debt and capital leases by debt instrument follows:



	September 30, 2016		December 31, 2015
Senior Secured Asset-Based Revolving Credit Facility:
Due February 2020; bearing interest at one-month LIBOR plus 2.25%	$	56,299	$	57,422
Tax-Exempt Bonds:
New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014 due December 2044 - fixed rate interest period through 2019, bearing interest at 3.75%	25,000		25,000
New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014R-2 due December 2044 - fixed rate interest period through 2026, bearing interest at 3.125%	15,000		—
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-2 due January 2025 - fixed rate interest period through 2017, bearing interest at 6.25%	21,400		21,400
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2015 due August 2035 - fixed rate interest period through 2025, bearing interest at 5.125%	15,000		15,000
Vermont Economic Development Authority Solid Waste Disposal Long-Term Revenue Bonds Series 2013 due April 2036 - fixed rate interest period through 2018, bearing interest at 4.75%	16,000		16,000
Business Finance Authority of the State of New Hampshire Solid Waste Disposal Revenue Bonds Series 2013 due April 2029 - fixed rate interest period through 2019, bearing interest at 4.00%	11,000		11,000
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-1; letter of credit backed due January 2025 - variable rate interest period through 2017, bearing interest at SIFMA Index	3,600		3,600
Other:
Capital leases maturing through April 2023, bearing interest at up to 7.70%	5,287		4,130
Notes payable maturing through January 2021, bearing interest at up to 7.00%	1,143		1,167
Senior Subordinated Notes:
Due February 2019; bearing interest at 7.75%	345,570		370,300
Principal amount of long-term debt and capital leases	515,299		525,019
Less—unamortized discount and debt issuance costs (1)	14,698		17,586
Long-term debt and capital leases less unamortized discount and debt issuance costs	500,601		507,433
Less—current maturities of long-term debt	1,562		1,448
	$	499,039	$	505,985


(1)	A summary of unamortized discount and debt issuance costs by debt instrument follows:



	September 30, 2016		December 31, 2015
Senior Secured Asset-Based Revolving Credit Facility	$	4,637	$	5,593
New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014	1,267		1,407
New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014R-2	586		—
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-2	518		566
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2015	778		830
Vermont Economic Development Authority Solid Waste Disposal Long-Term Revenue Bonds Series 2013	612		636
Business Finance Authority of the State of New Hampshire Solid Waste Disposal Revenue Bonds Series 2013	595		690
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-1	32		35
Senior Subordinated Notes	5,673		7,829
	$	14,698	$	17,586