Fair Value of Financial Instruments - Assets and Liabilities at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Assets:
Derivative financial instruments, asset	$ 0	$ 1,714
Liabilities:
Derivative financial instruments, liability	4,254	2,888
Fair Value, Measurements, Recurring
Assets:
Derivative financial instruments, asset	0	1,714
Liabilities:
Derivative financial instruments, liability	4,254	2,888
Fair Value, Measurements, Recurring | Level 1
Assets:
Derivative financial instruments, asset	0	0
Liabilities:
Derivative financial instruments, liability	0	0
Fair Value, Measurements, Recurring | Level 2
Assets:
Derivative financial instruments, asset	0	1,714
Liabilities:
Derivative financial instruments, liability	4,254	2,888
Fair Value, Measurements, Recurring | Level 3
Assets:
Derivative financial instruments, asset	0	0
Liabilities:
Derivative financial instruments, liability	$ 0	$ 0