Summary of Significant Accounting Policies - Long-term Asset Related to Jamul Tribe (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2017	Sep. 30, 2017	Dec. 31, 2016
Receivables - Loans and Debt Securities Acquired with Deteriorated Credit Quality
Provision expense for estimated loan loss reserve	$ 6,300	$ 11,900
Financing loan receivable, reserve allowance	11,926	11,926	$ 0
Financing loan receivable, unpaid principal balance		98,200	98,000
Loans to the Jamul Tribe	$ 75,478	75,478	$ 91,401
Delayed Draw Term Loan C Facility Commitments
Receivables - Loans and Debt Securities Acquired with Deteriorated Credit Quality
Additional borrowing capacity under the financing facility		$ 30,000

The contingent increase above the maximum borrowing capacity under the financing facility to fund certain costs.

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- Definition

Amount of unpaid principal balance of financing loan receivables.

+ References

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date more than one year from the balance sheet date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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