12 Month Trailing EBITDA

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- Definition

12 Month Trailing EBITDA Minimum (High End)

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- Definition

12 Month Trailing EBITDA Minimum (Low End)

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- Definition

Borrowing Threshold

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- Definition

Borrowing Threshold Percentage

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Debt Instrument, Amortization Rate

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Debt Instrument Increase in Maximum Borrowing Capacity

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- Definition

Debt Instrument Prepayment Premium

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- Definition

Debt Instrument, Upfront Fees

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- Definition

Equity Interest Pledge

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Excess Cashflow Threshold Percentage

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- Definition

Minimum liquidity required by credit facility

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No definition available.

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- Definition

Repurchase Percentage Price Of Aggregate Principal Due To Change In Control

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- Definition

Unpaid Indebtness After Maturity Or Acceleration

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Unpaid Judgment Or Decree

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Indebtedness divided by net capital.

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No definition available.

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- Definition

Percentage of tier one capital to total leverage exposure, as defined by regulatory framework.

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Debt And Liquidity (Narrative) (Details) - USD ($)				6 Months Ended
Debt And Liquidity (Narrative) (Details) - USD ($)	Apr. 19, 2018	Feb. 12, 2018	Feb. 27, 2015	Jun. 30, 2018	Jun. 15, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016	Apr. 27, 2016	Aug. 11, 2015	Jul. 28, 2015	Apr. 23, 2014	Nov. 20, 2012
Debt Instrument [Line Items]
Long-term Debt				$ 2,210,006,000			$ 339,374,000		$ 365,432,000
Minimum Liquidity										$ 25,000,000
Outstanding letters of credit							$ 8,700,000		12,300,000
Stated interest rate							6.375%
Loan balance, net of unamortized discount				106,378,000			$ 16,474,000		8,852,000
12 Month Trailing EBITDA							75,000,000
12 Month Trailing EBITDA Minimum (Low End)										40,000,000
12 Month Trailing EBITDA Minimum (High End)										35,000,000
Equity interest pledge						65.00%
Senior Notes
Debt Instrument [Line Items]
Long-term Debt				$ 0			$ 280,586,000		274,132,000
Principal amount issued														$ 300,000,000
Stated interest rate							6.375%							6.375%
Repurchase price, percentage of principal, due to change in control														101.00%
Debt Instrument, Redemption Price, Percentage				101.594%
Minimum
Debt Instrument [Line Items]
Unpaid judgment or decree in excess of							$ 50,000,000
Minimum \| Senior Notes
Debt Instrument [Line Items]
Unpaid indebtedness or accelerated proceeds exceeds								$ 50,000,000
Unpaid judgment or decree in excess of								$ 50,000,000
Amended and Restated Credit Agreement \| Minimum
Debt Instrument [Line Items]
Undrawn commitment fee			0.35%
Amended and Restated Credit Agreement \| Maximum
Debt Instrument [Line Items]
Undrawn commitment fee			0.70%
Amended and Restated Credit Agreement \| LIBOR \| Minimum
Debt Instrument [Line Items]
Margin spread on variable interest rate			2.25%
Amended and Restated Credit Agreement \| LIBOR \| Maximum
Debt Instrument [Line Items]
Margin spread on variable interest rate			4.75%
2018 Credit Agreement
Debt Instrument [Line Items]
Leverage ratio						4.00
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term Line of Credit				$ 0			58,192,000		$ 90,731,000
Revolving Credit Facility \| Amended and Restated Credit Agreement
Debt Instrument [Line Items]
Borrowing capacity													$ 400,000,000
Revolving Credit Facility \| Amended and Restated Credit Agreement July 2015 [Member]
Debt Instrument [Line Items]
Borrowing capacity										$ 225,000,000		$ 375,000,000
Long-term Line of Credit							39,500,000
Outstanding letters of credit							8,700,000
Revolving Credit Facility \| 2018 Revolving Credit Facility
Debt Instrument [Line Items]
Borrowing capacity		$ 250,000,000			$ 2,250,000,000	$ 1,500,000,000
Borrowing threshold (greater than)						$ 35,000,000
Borrowing threshold percentage						35.00%
Increase in borrowing capacity					$ 750,000,000
Debt instrument, upfront fees					1.00%
Revolving Credit Facility \| 2018 Revolving Credit Facility \| LIBO
Debt Instrument [Line Items]
Margin spread on variable interest rate		3.75%
Revolving Credit Facility \| 2018 Revolving Credit Facility \| ABR
Debt Instrument [Line Items]
Margin spread on variable interest rate		2.75%
Term Loan Facility \| Amended and Restated Credit Agreement July 2015 [Member]
Debt Instrument [Line Items]
Borrowing capacity												$ 40,000,000
Long-term Line of Credit							$ 19,000,000				$ 40,000,000
Line of Credit \| 2018 Term Loan Facility
Debt Instrument [Line Items]
Borrowing capacity		$ 1,500,000,000
Margin spread on variable interest rate				0.25%
Debt Instrument, Amortization Rate						5.00%
Prepayment premium						1.00%
Excess Cashflow Threshold Percentage						75.00%
Line of Credit \| 2018 Term Loan Facility \| Contingent Event One
Debt Instrument [Line Items]
Excess Cashflow Threshold Percentage						50.00%
Line of Credit \| 2018 Term Loan Facility \| Contingent Event Two
Debt Instrument [Line Items]
Excess Cashflow Threshold Percentage						0.00%
Leverage ratio						1.25
Line of Credit \| 2018 Term Loan Facility \| Minimum \| Contingent Event One
Debt Instrument [Line Items]
Leverage ratio						1.25
Line of Credit \| 2018 Term Loan Facility \| Maximum \| Contingent Event One
Debt Instrument [Line Items]
Leverage ratio						1.75
Line of Credit \| 2018 Term Loan Facility \| LIBO
Debt Instrument [Line Items]
Margin spread on variable interest rate		3.50%
Undrawn commitment fee		0.25%
Line of Credit \| 2018 Term Loan Facility \| ABR
Debt Instrument [Line Items]
Margin spread on variable interest rate		2.50%
Brookfield \| Maximum
Debt Instrument [Line Items]
Leverage ratio	175.00%
Brookfield \| Brookfield Promissory Note [Member]
Debt Instrument [Line Items]
Dividends Payable	$ 750,000,000
Brookfield \| Brookfield Promissory Note [Member] \| Maximum
Debt Instrument [Line Items]
Leverage ratio	175.00%
Brookfield \| Brookfield Promissory Note [Member] \| LIBO
Debt Instrument [Line Items]
Margin spread on variable interest rate	4.50%
Third Anniversary \| Brookfield \| Brookfield Promissory Note [Member] \| LIBO
Debt Instrument [Line Items]
Margin spread on variable interest rate	2.00%