Debt and Interest Expense (Tables)

3 Months Ended

Mar. 31, 2018

Debt Instruments [Abstract]

Debt Outstanding and Debt Activity Tables

The following table presents WES and WGP’s outstanding debt:

	March 31, 2018						December 31, 2017
thousands	Principal		Carrying Value		Fair Value(1)		Principal		Carrying Value		Fair Value (1)
Short-term debt
WGP RCF	$	28,000	$	28,000	$	28,000	$	—	$	—	$	—
Long-term debt
WGP RCF	$	—	$	—	$	—	$	28,000	$	28,000	$	28,000
2018 Notes	350,000		349,810		349,542		350,000		349,684		350,631
2021 Notes	500,000		496,095		522,069		500,000		495,815		530,647
2022 Notes	670,000		668,906		670,857		670,000		668,849		684,043
2025 Notes	500,000		492,120		487,240		500,000		491,885		500,885
2026 Notes	500,000		495,360		508,551		500,000		495,245		520,144
2028 Notes	400,000		394,285		401,807		—		—		—
2044 Notes	600,000		593,262		605,816		600,000		593,234		637,827
2048 Notes	700,000		686,508		698,234		—		—		—
WES RCF	—		—		—		370,000		370,000		370,000
Total long-term debt	$	4,220,000	$	4,176,346	$	4,244,116	$	3,518,000	$	3,492,712	$	3,622,177

⁽¹⁾  Fair value is measured using the market approach and Level 2 inputs.

Debt activity. The following table presents WES and WGP’s debt activity for the three months ended March 31, 2018:

thousands	Carrying Value
Balance at December 31, 2017	$	3,492,712
WES RCF borrowings	260,000
Issuance of 2028 Notes	400,000
Issuance of 2048 Notes	700,000
Repayments of WES RCF borrowings	(630,000		)
Other	(18,366		)
Balance at March 31, 2018	$	4,204,346

Interest Expense Table

The following table summarizes the amounts included in interest expense:

	Three Months Ended   March 31,
thousands	2018			2017
Third parties
Long-term and short-term debt	$	(41,536	)	$	(34,814	)
Amortization of debt issuance costs and commitment fees	(2,864		)	(1,964		)
Capitalized interest	4,054			816
Total interest expense – third parties	(40,346		)	(35,962		)
Affiliates
Deferred purchase price obligation – Anadarko (1)	—			(71		)
Total interest expense – affiliates	—			(71		)
Interest expense	$	(40,346	)	$	(36,033	)

⁽¹⁾  See Note 3 for a discussion of the Deferred purchase price obligation - Anadarko.