Commitments and Contingencies Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2015

Commitments and Contingencies Disclosure [Abstract]

Contractual Obligation, Fiscal Year Maturity Schedule [Table Text Block]

The annual minimum payments for the next five years and total minimum payments thereafter are presented below:

Years Ending December 31,	Amount (1) (in thousands)
2016	$	132,747
2017	128,074
2018	131,489
2019	142,161
2020	141,854
Thereafter	288,113
Total	$	964,438

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(1) During the third quarter of 2015, the Company vacated its office space in Tulsa, Oklahoma. These amounts include lease payments for the Tulsa office, net of sublease income. The Company expects to receive $3.5 million of sublease income as follows: $831,000 in 2016, $953,000 in 2017, $978,000 in 2018, and $741,000 in 2019.