Fair Value Measures (Tables)

6 Months Ended

Jun. 30, 2014

Estimated Fair Values Determined Using Available Market Information and Valuation Methodologies

The fair value of debt is the estimated amount the Partnership would have to pay to repurchase its debt, including any premium or discount attributable to the difference between the stated interest rate and market rate of interest at the balance sheet date. Fair values are based on quoted market prices or average valuations of similar debt instruments at the balance sheet date for those debt instruments for which quoted market prices are not available. Estimated fair values are determined by using available market information and valuation methodologies. Considerable judgment is required in interpreting market data to develop the estimates of fair value. The use of different market assumptions or valuation methodologies may have a material effect on the estimated fair value amounts.

	June 30, 2014				December 31, 2013
	Carrying amount		Fair value (Level 2)		Carrying amount		Fair value (Level 2)
	($ in thousands)
Financial liabilities:
Revolving credit facility	$	150,000	$	150,000	$	343,500	$	343,500
Premium on 2021 Notes		5,397		5,397		5,730		5,730
2021 Notes		750,000		805,313		750,000		801,098
2022 Notes		750,000		827,813		750,000		804,848
2023 Notes		1,400,000		1,477,882		1,400,000		1,355,382
2024 Notes		750,000		794,063		—		—