Debt

Consolidated debt at December 31, 2015 and March 31, 2016 was as follows (in thousands, except as otherwise noted):



	December 31, 2015			March 31, 2016			Weighted-Average Interest Rate for the Three Months Ended March 31, 2016 ⁽¹⁾
Commercial paper⁽²⁾	$	279,961		$	—		0.7%
$250.0 million of 5.65% Notes due 2016⁽³⁾	250,335			250,229			5.7%
$250.0 million of 6.40% Notes due 2018	255,215			254,698			5.5%
$550.0 million of 6.55% Notes due 2019	564,116			563,161			5.7%
$550.0 million of 4.25% Notes due 2021	555,362			555,121			4.0%
$250.0 million of 3.20% Notes due 2025	249,700			249,707			3.2%
$650.0 million of 5.00% Notes due 2026⁽²⁾	—			649,193			5.0%
$250.0 million of 6.40% Notes due 2037	249,036			249,042			6.4%
$250.0 million of 4.20% Notes due 2042	248,437			248,445			4.2%
$550.0 million of 5.15% Notes due 2043	556,218			556,192			5.1%
$250.0 million of 4.20% Notes due 2045	249,914			249,914			4.6%
Total debt, excluding unamortized debt issuance costs	3,458,294			3,825,702			4.6%
Unamortized debt issuance costs	(18,672		)	(23,441		)
Less: current portion of long-term debt	250,335			250,229
Total long-term debt	$	3,189,287		$	3,552,032


(1)	Weighted-average interest rate includes the amortization/accretion of discounts, premiums and gains/losses realized on historical cash flow and fair value hedges recognized as interest expense.


(2)	These borrowings were outstanding for only a portion of the three-month period ending March 31, 2016. The weighted-average interest rate for these borrowings was calculated based on the number of days the borrowings were outstanding during the noted period.


(3)	These borrowings will mature in October 2016 and are included with current debt on our consolidated balance sheets at December 31, 2015 and March 31, 2016.

All of the instruments detailed in the table above are senior indebtedness.

The face value of our debt at December 31, 2015 and March 31, 2016 was $3.4 billion and $3.8 billion, respectively. The difference between the face value and carrying value of our debt outstanding is the unamortized portion of terminated fair value hedges and the unamortized discounts and premiums on debt issuances. Realized gains and losses on fair value hedges and note discounts and premiums are being amortized or accreted to the applicable notes over the respective lives of those notes.

2016 Debt Offering

In February 2016, we issued $650.0 million of our 5.00% notes due 2026 in an underwritten public offering. The notes were issued at 99.875% of par. Net proceeds from this offering were approximately $644.0 million, after underwriting discounts and offering expenses of $5.3 million. The net proceeds from this offering were or will be used to repay borrowings outstanding under our commercial paper program and for general partnership purposes, including expansion capital.

Other Debt

Revolving Credit Facilities. At March 31, 2016, the total borrowing capacity under our revolving credit facility with a maturity date of October 27, 2020 was $1.0 billion. Any borrowings outstanding under this facility are classified as long-term debt on our consolidated balance sheets. Borrowings under this facility are unsecured and bear interest at LIBOR plus a spread ranging from 1.000% to 1.625% based on our credit ratings. Additionally, an unused commitment fee is assessed at a rate between 0.100% and 0.275% depending on our credit ratings. The unused commitment fee was 0.125% at March 31, 2016. Borrowings under this facility may be used for general partnership purposes, including capital expenditures. As of March 31, 2016, there were no borrowings outstanding under this facility with $6.3 million obligated for letters of credit. Amounts obligated for letters of credit are not reflected as debt on our consolidated balance sheets, but decrease our borrowing capacity under this facility.

At March 31, 2016, the total borrowing capacity under our 364-day credit facility was $250.0 million. This credit facility matures on October 25, 2016, subject to a term-out option. We may exercise the term-out option no later than 30 days prior to October 25, 2016 and elect to have all outstanding borrowings converted into a term loan due and payable on October 25, 2018, subject to the payment of a term-out fee. Any borrowings under this credit facility are classified as current debt on our consolidated balance sheets. Borrowings under this facility are unsecured and bear interest at LIBOR plus a spread ranging from 1.000% to 1.625% based on our credit ratings. Additionally, an unused commitment fee is assessed at a rate between 0.080% and 0.225% depending on our credit ratings. The unused commitment fee was 0.100% at March 31, 2016. Borrowings under this facility may be used for general partnership purposes, including capital expenditures. As of March 31, 2016, there were no borrowings outstanding under this facility.

Commercial Paper Program. The maturities of our commercial paper notes vary, but may not exceed 397 days from the date of issuance. The commercial paper notes are sold under customary terms in the commercial paper market and are issued at a discount from par, or alternatively, are sold at par and bear varying interest rates on a fixed or floating basis. The commercial paper we can issue is limited by the amounts available under our revolving credit facility up to an aggregate principal amount of $1.0 billion and is classified as long-term debt.