Line of Credit Facility, Additional Borrowing Capacity, Available

No definition available.

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- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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- Definition

Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Amount of assets pledged to secure a debt instrument.

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

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

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

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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

Amount, after accumulated amortization, of debt premium.

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- Definition

Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

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No definition available.

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Amount of advances from the Federal Home Loan Bank (FHLB).

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- Definition

Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Amount of the cost of borrowed funds accounted for as interest expense.

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- Definition

Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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- Definition

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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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Debt (Details) - USD ($)			3 Months Ended		9 Months Ended
Debt (Details) - USD ($)	Jul. 02, 2018	Jun. 29, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term Debt, Gross			$ 1,123,700,000		$ 1,123,700,000				$ 592,300,000
Debt Instrument, Collateral Amount			15,900,000		15,900,000
Interest Expense			13,400,000	$ 7,800,000	29,300,000	$ 26,900,000
Interest Paid, Including Capitalized Interest, Operating and Investing Activities			19,700,000	$ 12,700,000	35,000,000	$ 31,800,000
Secured Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount			250,000,000		250,000,000
Long-term Debt, Gross			249,400,000		249,400,000				0
Proceeds from Debt, Net of Issuance Costs		$ 249,400,000
Senior Notes [Member] \| Senior Note Due on September Nineteen,Twenty Twenty Two [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			281,700,000		281,700,000				0
Senior Notes [Member] \| Senior Notes, 4.35 Percent Due February 15, 2025 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			448,400,000		448,400,000				448,100,000
Subordinated Debt [Member] \| Subordinated Debenture, 7.375 Percent Due 2054 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross			144,200,000		144,200,000				144,200,000
Notes Payable under Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Amount Outstanding			0		0				0
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			300,000,000		300,000,000				225,000,000
Revolving Credit Facility [Member] \| Credit facility and Secured Loan [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Additional Borrowing Capacity, Available			100,000,000		100,000,000
Federal Home Loan Bank of Dallas [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances									0
Federal Home Loan Bank Stock			3,300,000		3,300,000				3,300,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances							$ 55,000,000
Federal Home Loan Bank of Chicago [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances			10,000,000		10,000,000				0
Federal Home Loan Bank Stock			800,000		800,000				400,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances							$ 55,000,000	$ 10,000,000
Federal Home Loan Bank Borrowings, Fair Value Disclosure			10,000,000		10,000,000				$ 0
Infinity [Member]
Debt Instrument [Line Items]
Business Combination, Consideration Transferred, Liabilities Incurred	$ 110,000,000
Infinity [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Business Combination, Consideration Transferred, Liabilities Incurred	250,000,000
Infinity [Member] \| Senior Notes [Member] \| Senior Note Due on September Nineteen,Twenty Twenty Two [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Premium	7,100,000
Debt Instrument, Face Amount			$ 275,000,000		$ 275,000,000
Debt Instrument, Interest Rate, Stated Percentage			5.00%		5.00%
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt	$ (282,100,000)
Debt Instrument, Interest Rate, Effective Percentage			4.36%		4.36%